Docs286863768344basic of computer by itcoolboy9

BY : SIRNATEC IT CENTRE

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Table Of Contents Chapter 1 Chapter 2

Computer Introduction Functional of Computer Hardware

Chapter 1 Computer Introduction

Chapter 1 - Computer Introduction 1.1) What is Computer? ◦ Machine response to Instruction & Executed ◦ Design by Charles Babbage on 1823

1.2) Type of Computers

Ultra Mobile PC (UMPC)

Server PC

Tablet PC

Workstation

Laptop/Notebook

Desktop PC

Personal Digital Assistant (PDA)

1.3) What inside the Computer? ◦ ◦ ◦ ◦ ◦ ◦ ◦

CPU (Processor) Memory (RAM) Motherboard Power Supply Chassis/Based Unit Storage Devices (HDD/FDD/ODD) Output Devices (Video Display, Printer, Speakers, Modem, USB Ports) ◦ Input Devices (Keyboard/Mouse, Scanner, Joystick)

1.3) What inside the Computer (continue)

Chapter 2 Functional of Computer Hardware

Chapter 2 - Functional of Computer System 2.1 Chassis (Casing) 2.1.1) What is Chassis? - â&#x20AC;&#x153;Homeâ&#x20AC;? for Computer Components 2.1.2) What inside Chassis?

2.1 Chassis 2.1.3) Type of Chassis (Form Factor) •

•

BTX (Balance Technology Extended) Family - BTX - Micro BTX - Pico BTX ATX (Advance Technology Extended) Family - ATX - Micro ATX - Flex ATX

Micro ATX/BTX

ATX/BTX

Flex ATX/Pico BTX Copyright@2008 Sirnatec IT Centre

2.1 Chassis 2.1.4) Dimension & Supported Motherboard Form Factor

Max. Width Allowance

Max. Depth Allowance

Supported Motherboard

BTX

311mm (12.8”)

243mm (10”)

1) BTX 2) Micro BTX 3) Pico BTX

Micro BTX

253mm (10.4”)

255mm (10.5”)

1) Micro BTX 2) Pico BTX

Pico BTX

219mm (9”)

255mm (10.5”)

1) Pico BTX

Micro ATX

244mm (9.6”)

1) Micro ATX 2) Flex ATX

Flex ATX

229mm (9”)

191mm (7.5”)

Flex ATX

ATX

305mm (12”)

244mm (9.6”)

1) ATX 2) Micro ATX 3) Flex ATX

2.1 Chassis 2.1.5) Main different Between ATX & BTX â&#x20AC;˘ Motherboard Layout -Components Placement -Back Panel Layout -Two Cooling Fans Card Slots

CPU

M E M O R Y

PSU

STORAGE DRIVES

BTX

ATX Copyright@2008 Sirnatec IT Centre

2.1 Chassis 2.1.6) Advantage of BTX • Thermal Environment - In-line, high-velocity, low temp airflow - Above and below mainboard airflow

• Acoustic Performance - Two-fan design - Lower impedance allows lower fan speed

• Mainboard - Balanced memory and I/O routing - 4-layer mainboard design

• Structural Integrity - 100% increase in heatsink mass (up to 1kg)

• Cost Structure - Steel case, standard components

BTX Chassis sample Copyright@2008 Sirnatec IT Centre

2.2 Motherboard 2.2.1) What is Motherboard? • Center Circuit Board or “Body” of Computer.

Body

2.2 Motherboard 2.2.2) What inside Motherboard? â&#x20AC;˘ Host CPU, RAM, HDD, ODD, FDD, Peripheral Cards,

Power Supply (Internal Connectors) SATA (Hard Disk/Optical Drive)

ATX (Power Supply)

IDE (Hard Disk/ Optical Drive)

F_Panel PCI (Peripheral Cards) DIMM (RAM) FDD (Floppy Drive) CPU ATX_12V (Power Supply) CPU_Fan

2.2 Motherboard 2.2.2) What inside Motherboard? (continue) â&#x20AC;˘ Host External Ports (Back Panel Connectors)

a) PS/2 Keyboard & PS/2 Mouse Port b) Parallel Port c) Serial Port d) D-Sub Port e) USB Port f) RJ-45 LAN Port g) Line In Jack (Blue) h) Line Out Jack (Green) i) Mic In Jack (Pink)

2.2 Motherboard 2.2.2) What inside Motherboard? (continue) â&#x20AC;˘

Host BIOS (Basic Input Output System)

CMOS Battery

POST Screen

2.2 Motherboard 2.2.3) Motherboard Form Factor Form Factors Size(mm) a)ATX b) Micro-ATX c) Flex-ATX d) BTX e) Mini-ITX f) Nano-ITX g) Pico-ITX

PCB 305x244 244x244 229x191 325x266 170x170 120x120 100x72

2.2 Motherboard 2.2.4) Block Diagram of Motherboard Center Processing Unit (CPU)

Graphics 2D/3D - PCI Express X16 - AGP 4X/8X - Graphics Accelerator ATA Interface - ODD/FDD ATA 133/100/66

Serial ATA Interface - HDD SATA

<etwork Interface - 10/100Mb LA< - Gb LA<

DDR/DDR2 RAM (400/533/667/800)

Graphics Memory Control Hub

IO Control Hub

USB 2.0/1.0 Ports - USB Devices (Mouse, Keyboard)

PCI Express x 1 - PCI Express Devices

High Definition Audio

2.2 Motherboard 2.2.5) Function of Motherboard • Through Chipset (Integrated Circuit) • Graphics Memory Controller Hub (GMCH) Memory (DDR2 RAM) (already move to CPU) Graphics/Video/Display Card (PCI Express x16 or AGP 8x/4x, Graphic controller) • Input Output Controller Hub (ICH) ATA (Optical Drive/Floppy Drive/ZIP Drive) SATA (Hard Drive/Optical Drive) Network (10/100Mb LAN, Gb LAN, Wireless LAN) USB Ports (Keyboard/Mouse/External Optical/Hard Drive/Pen Drive & others USB devices) IEEE Ports (Video camera & other IEEE devices) PCI Express x1 peripheral cards Audio (Audio codec/Speakers) Copyright@2008 Sirnatec IT Centre

2.2 Motherboard 2.2.6) Type of GMCH & ICH Intel 1) Desktop â&#x20AC;&#x201C; X58,P45, P35,G33,G31,G965

2.2 Motherboard 2.2.6) Type of GMCH & ICH (continue) Intel 2) Mobile –PM965, 945GM/PM, 915GM/GMS/PM,

Example – PM965 GMCH & ICH

2.2 Motherboard 2.2.6) Type of GMCH & ICH (continue) ◦ VIA

VIA North Bridge (GMCH) AMD – K8T900/K8T890/ K8N890/ Intel – PT890/ PT880 ULTRA

VIA South Bridge (ICH) VT8251/VT8237R/VT8237A

Example – PT890 North & South Bridge Copyright@2008 Sirnatec IT Centre

2.2 Motherboard 2.2.6) Type of GMCH & ICH (continue) ◦ SIS SIS (GMCH) AMD – 755 Intel – 672FX/662/656FX/649FX/656/655TX/655FX/648FX

SIS (ICH) Intel & AMD - 968

Example – SIS672FX & SIS968

2.2 Motherboard 2.2.7) Chipset Identification on Motherboard Brand Intel Intel Intel Gigabyte Gigabyte MSI

Model DX58SO DP45SG DP35DP GA-G33M-S2L GA-G31M-S2L P965 Neo-F V2

Chipset X58 P45 P35 G33 G31 P965

2.3 CPU (Center Processor Unit) 2.3.1) What is CPU? • • •

CPU stands for “Central Processing Unit” “Brain” of the computer which process the data Speed measured in Mhz (megahertz). 1 MHz=one million cycles per second

2.3 CPU (Center Processor Unit) 2.3.2) What is “Bus”? - “Road” which connect 2 or more devices in a computer

2.3.3) Type of “Bus” a) System bus or Front Side Bus (http://www.youtube.com/watch?v=n7jdjEuyljs)

- The physical bi-directional data bus that carries all electronic signal information between the central processing unit (CPU), RAM, Graphics and the Motherboard northbridge.

b) I/O bus - Connect between CPU to other components except RAM

2.3 CPU (Center Processor Unit) 2.3.3) Type of â&#x20AC;&#x153;Busâ&#x20AC;? (continue) c) Data bus - The bus (connections between and within the {CPU}, memory, and peripherals) used to carry {data}

d) Address bus - The connections between the {CPU} and memory which carry the {address/receiver} from/to which the CPU wishes to read or write.

2.3 CPU (Center Processor Unit) 2.3.4) Bus Size/Bus Bandwidth - Total amount of data that can theoretically be transferred on the bus in a given unit of time (also call number of lanes). - Express in bit/second (bps) or bytes/second for digital devices. - Express in cycle/second or herts (Hz) for analog devices. - Power of 2, 8, 16, 32 & 64

2.3 CPU (Center Processor Unit) 2.3.5) PC “Bus” Block Diagram

2.3 CPU (Center Processor Unit) 2.3.6) System Clock - Also call Bus Speed. - A faster clock speed will enable a processor to execute an instruction more quickly (http://www.youtube.com/watch?v=wjqe1eQx8vc) - The system clock is a circuit that emits a continuous stream of precise high and low pulses that are all exactly the same length. - One clock cycle is the time that passes from the start of one high pulse, until the start of the next cycle. - Measure in Mhz (megahertz â&#x20AC;&#x201C; million of cycles per second )

2.3 CPU (Center Processor Unit) 2.3.7) CPU Speed = CPU Multiplier x System Clock Note: System Clock = FSB/4 for Intel CPU & FSB/2 for AMD CPU

Example: Intel 3.2Ghz = 16 x 200Mhz AMD Athlon XP2700+ (2.17Mhz) = 13 x 166Mhz

2.3 CPU (Center Processor Unit) 2.3.8) What is Cache Memory? - CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory. - The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations (backpack

story)

L2 Cache Video clips

2.3 CPU (Center Processor Unit) 2.3.9) What inside CPU?

2.3 CPU (Center Processor Unit) 2.3.10) Function of CPU L2 Memory Cache - High speed Static RAM (SRAM) does not need to refresh - Larger then L1 Memory Cache - Provide data to CPU at speed 10x faster then DRAM

L1 Memory Cache - consists of Instruction & Data - input cache (smaller then L2 cache) - Instruction Cache is used for caching data from memory

2.3 CPU (Center Processor Unit) 2.3.10) Function of CPU (continue) Fetch Unit - Loading instruction from memory - look for L1 instruction cache first, if not it will go to L2 memory cache. If the instruction is not there, then it will directly load from the slow system RAM memory

2.3 CPU (Center Processor Unit) 2.3.10) Function of CPU (continue) Decoder Unit - Figure out what particular instruction are by consulting the ROM memory that exist inside the CPU call microcode. - The microcode will teach CPU what to do. - Add a+b, the microcode will tell decoder that it need 2 parameter a & b. - The decoder then require fetch unit to grab the data present in the next 2 memory position. - Decoder unit will pass all data & step by step process on how to execute that instruction to the execute unit Copyright@2008 Sirnatec IT Centre

2.3 CPU (Center Processor Unit) 2.3.10) Function of CPU (continue) Execute Unit - To execute the instruction given.

L1 Data Cache - In charge of sending the result back to RAM memory or another place, such as video card

2.3 CPU (Center Processor Unit) 2.3.11) Block Diagram of CPU

2.3 CPU (Center Processor Unit) 2.3.11) Block Diagram of CPU (continue)

2.3 CPU (Center Processor Unit) 2.3.12) CPU Socket - Connector on motherboard that accepts CPU & forms an electrical interface with it. 2.3.13) Type of CPU Socket a) Intel - Socket 1366 (Desktop) - Socket 775/LGA 775 (Desktop) - Socket M (Mobile-Intel Core 2 Duo)

Socket 775

Socket M

b) AMD - AM3+ (Desktop) - AM2+ (Desktop) - Socket S1 (Mobile) - Socket 563 (Mobile)

Socket AM2+

Socket S1

2.3 CPU (Center Processor Unit) 2.3.14) Intel CPU Architecture â&#x20AC;˘ Intel Core micro architecture - base on Pentium M arc/P6 such as core solo (65nm), core duo (yonah, dual core 65nm)

â&#x20AC;˘ Intel Pentium 4 Architecture -7th generation x86 architecture

2.3 CPU (Center Processor Unit) 2.3.15) Duo Core Technology

In a single core processor, this â&#x20AC;&#x153;performance engine? takes in raw data and turns it into either video, movies, Music, digital-photos, games, email, or other rich multimedia content

In a dual-core computer chip, there are two â&#x20AC;&#x153;performance engines? that can take more data and simultaneously process the data into rich multimedia content at a faster rate.

Video Clips

2.3 CPU (Center Processor Unit) 2.3.15) Duo Core Technology (continue)

Core i7 Circuitry

2.3 CPU (Center Processor Unit) 2.3.16) Type of CPU •

Intel® Core TM i7 processor - Quad-core,8MB L3 cache,2.93 GHz, 4.8GT/s QPI

•

Intel® Core TM 2 Quad processor - Quad-core, 8MB L2 cache, 2.40 GHz, 1066 MHz FSB

•

Intel® CoreTM 2 Extreme processor - Quad-core/Dual-core, 8MB L2 cache, 2.93 GHz, 1066 MHz FSB

•

Intel® CoreTM 2 Duo processor - Dual-core, 4MB L2 cache, 2.66 GHz, 1066 MHz FSB

•

Intel® Pentium D processor with dual core technology - Dual-core, 2x2MB L2 cache, 3.60 GHz, 800 MHz FSB Copyright@2008 Sirnatec IT Centre

2.3 CPU (Center Processor Unit) 2.3.16) Type of CPU (continue) •

Intel® Pentium® 4 processor supporting HyperThreading Technology† or greater - 2MB L2 cache, 3.80 GHz, 800 MHz FSB

•

Intel® Celeron® D processor - 512KB L2 cache, 3.60 GHz, 533 MHz FSB

•

Intel® Celeron® M processor - 1MB L2 cache, 2.00 GHz, 533 MHz FSB

•

Intel® Pentium® processor Extreme Edition - Dual-core, 2x2MB L2 cache, 3.73 GHz, 1066 MHz FSB

2.3 CPU (Center Processor Unit) 2.1.16) Type of CPU (continue) •

AMD Phenom TM II X3 - 512MB L2 cache, 2.80 GHz, 64 bits technology

•

AMD Athlon TM 64 processor - 1MB L2 cache, 2.60 GHz, 64 bits technology

•

AMD Athlon TM 64 FX processor - Dual-core, 2MB L2 cache, 2.80 GHz, 64 bits technology

•

AMD Athlon TM 64 X2 Dual-Core processor - Dual-core, 2MB L2 cache, 3.00 GHz, 64 bits technology

•

AMD Athlon Sempron processor

•

AMD Turion™ 64 X2 Dual-Core Mobile Technology

•

AMD Turion 64 Mobile Technology

2.3 CPU (Center Processor Unit) 2.3.17) CPU Model Identification

Video Clips

2.3 CPU (Center Processor Unit) 2.3.17) CPU Model Identification (continue)

2.4 Memory 2.4.1) What is Memory? •

• •

Act as a “Foot Solder” for the CPU which are use to stores information from the OS, applications & data (like Memory in our brain). Quickly accessible to be used for decision making by CPU Size measured in MBs (megabyte). 1 MBs=one million bytes of information

2.4 Memory 2.4.2) Type of Memory â&#x2014;Ś RAM (Random Access Memory) - Read & write memory - Need power to stored data

â&#x2014;Ś ROM (Read Only Memory) - Read only memory - To stored that boot the computers & perform diagnostics - Holds data even when it is not powered

2.4 Memory Type of RAM ◦ SRAM (Static RAM) - Used for high speed memory call L2 cache memory - Faster & more expensive then DRAM - Speed between 8 & 12ns - Synchronous & asynchronous - Does not require refresh operation ◦ DRAM (Dynamic RAM) - Use in computer main memory - Must refresh every 2ms

2.4 Memory Type of DRAM ◦ SDRAM (Synchronous DRAM) -

Transfer its commands, address & data on the rising edge of the clock Transfer one data words per clock cycle Consume more power 3.3v 168 pins

◦ DDR SDRAM (Double Data Rate RAM)

Transfer the commands, address & data on both rising & falling edge of the clock. - Consume less power 2.5v - 184 pins

2.4 Memory Type of ROM ◦ PROM (Programmable ROM) - Only programmable once

◦ EPROM (Erasable Programmable ROM) - Able to program multiples times - Can be erased but need to remove from devices

◦ EEPROM (Electrically Erasable Programmable ROM) - Able to program multiples times - Can be erased & do not need to remove from devices

2.4 Memory Type of ROM (continue) â&#x2014;Ś Flash Memory - Type of EEPROM - Use in-circuit writing to erase by applying an electrical field to the entire chip or blocks - Faster then EEPROM because it writes data in chunks, usually 512 bytes in size, instead of a byte at a time

â&#x2014;Ś CMOS (Complementary Metal-Oxide Semiconductor) - Store system setup information

2.4 Memory 2.4.3) Memory Block diagram & Function - CPU request data from RAM, it place the address of the location on the data bus & wait the request data bus to show up. - The CPU grab the data in 32 / 64 bits chunks depend on the width of data bus. - The CPU grabs 8 bytes of data at a time.

<http://www.howstuffworks.com/ram.htm> Copyright@2008 Sirnatec IT Centre

2.4 Memory 2.4.3) Memory Block diagram & Function (continue)

The capacitor in a dynamic RAM memoy cell is like a leaky bucket. It needs to be refreshed periodically or it will discharge to 0

Memory is made up of bits arranged in a two-dimensional Grid. In this figure, red cells represent 1s and white cells Represent 0s. In the animation, a column is selected and then Rows are charged to write data into the specific column

2.4 Memory 2.4.4) Memory Pyramid

2.4 Memory 2.4.5) RAM Module ◦ DIMM (Dual In-Line Memory Module) -

Soldered onto a modular PCB 168 pins (SDRAM),184 pins (DDR RAM), 240 pins (DDR2 RAM) 5.4 x 1” Capacity up to 2GB/module 64 bits data bus

168 pins DIMM

2.4 Memory 2.4.5) RAM Module (continue) ◦ SIMM (Single In-Line Memory Module)

Soldered onto a modular PCB 30 & 72 pin connector 3.5 x 7.5 “ (30 pin) 4.25 x 1” (72 pin) Capacity up to 256MB/module 32 bits data bus

72 pins SIMM

30 pins SIMM

2.4 Memory 2.4.5) RAM Module (continue) ◦ SODIMM (Small Outline Dual-In Memory Module) -

Soldered onto a modular PCB 72, 144 & 200 pins 2.1 x 1” Capacity up to 16 to 2GB/module 32 bits (72 pins), 64 bits (144 pins) data bus

72 pins SODIMM

144 pins SODIMM

2.4 Memory 2.4.5) RAM Module (continue) â&#x2014;Ś RIMM (Rambus In-Line Memory Module) -

Soldered onto a modular PCB Similar size & pin configuration as DIMM High speed data bus call Rambus Channel (16 bits chunks) Generate lot of heats Heat Spreader to prevent overheating Capacity up to 256MB 32 bits data bus

184 pins RIMM

2.4 Memory 2.4.6) DDR SDRAM Technology â&#x2014;Ś DDR3 SDRAM

(DOUBLE DATA RATE three SYNCHRONOUS DRAM)

Higher bandwidth (up to 1600 MHz) Performance increase at low power Longer battery life in laptops Enhanced low power features and thermal design

2.4 Memory 2.4.6) DDR SDRAM Technology (continue)

2.4 Memory 2.4.7) DDR SDRAM Module â&#x2014;Ś DDR3 SDRAM

Peak transfer rate = number of bits x clock/8

2.4 Memory 2.4.7) DDR SDRAM Module (continue) â&#x2014;Ś DDR2 SDRAM

Peak transfer rate = number of bits x clock/8 http://www.simmtester.com/page/news/showpubnews.asp?num=150

2.4 Memory 2.4.8) Flash Memory Technology a) What is Flash Memory? - Type of EEPROM chip - Storage devices for digital camera, mobile phone & video games consoles - Solid stage storage devices (electronics)

b) Type of Flash Memory - Removable Flash Memory (Memory Stick, CompactFlash, SmartMedia, SD card, PCMCIA type I & II), USB Flash Drive (integrated with USB connector) - Non Removable Flash Memory (BIOS chip-CMOS).

2.4 Memory 2.4.8) Flash Memory Technology c) How Flash Memory Works? - Grid of columns & rows with a cell that has two transistors at each intersection. - Two transistors (floating gate & control gate) are separated by a thin oxide layer. - Floating gate only link to the row/wordline. - The cell has a value on 1 as long as the link is in place.

2.4 Memory 2.4.8) Flash Memory Technology c) How Flash Memory Works? (continue)

2.4 Memory 2.4.8) Flash Memory Technology c) How Flash Memory Works â&#x20AC;&#x201C; Tunneling

(continue)

- Tunneling is used to alter the placement of electrons in the floating gate. - 10 to 13 volts electrical charge (come from the coloum/bitline) is applied to the floating gate. - This charge causes the floating-gate transistor act line an electron gun. - The electrons are pushed through & trapped on other side of thin oxide layer to become negative charges. - This negative charge electrons acts as a barrier between the control gate & floating gate. - Cell sensor monitors the level of charge passing through the floating gate. - If the flow through the gate > 50% of the charge, it has a value of 1. - If the charge passing through drop below 50% threshold, the value changes Copyright@2008 Sirnatec IT Centre 70 to 0.

2.4 Memory 2.4.8) Flash Memory Technology c) How Flash Memory Works â&#x20AC;&#x201C; Erasing

(continue)

- Electric field or high-voltage charge is applied for erasing process. - Flash memory uses in-circuit wiring to apply the electric field either entire chip or predetermined sections known as blocks.

2.4 Memory 2.4.8) Flash Memory Technology d) Removable Flash Memory Cards

2.4 Memory 2.4.8) Flash Memory Technology d) Removable Flash Memory Cards (continue)

2.4 Memory 2.4.8) Flash Memory Technology e) Removable USB Flash Memory Drive (Pen Drive) - USB data storage devices - Removable & rewritable - 1-4 inches length - less than 56g weight - Storage capacity up to 16GB - Transfer speed about 3MB/s

2.4 Memory 2.4.8) Flash Memory Technology e) Removable USB Flash Memory Drive (Pen Drive) What is Universal Serial Bus (USB)? - Serial Bus standard to interface devices. - Replaced Serial & Parallel ports. - Connect mouse, keyboard, PDAs, joysticks, scanners, printers, digital camera & flash drive (Pen drive).

2.4 Memory 2.4.8) Flash Memory Technology e) Removable USB Flash Memory Drive (Pen Drive) I) What Inside USB Flash Memory Drive 1) USB Connector – provides an interface to host computer 2) USB mass storage controller device – implements the USB host controller 3) Test points – for testing/loading code into microprocessor 4) Flash memory chip – stored data 5) Crystal oscillator – produces main 12MHz clock signal & control data output. 6) LED – indicate data transfer/reads and writes 7) Write-protect switch – “write-protection” mode indication 8) Space for 2nd flash memory chip

2.4 Memory 2.4.8) Flash Memory Technology e) Removable USB Flash Memory Drive (Pen Drive) II) Common Application - Personal data transport - System administration - Computer repair - To boot operating system - Window Vista ReadyBoost - Audio players - Music storage - Backup

2.4 Memory 2.4.9) How much memory do I need?

2.5 Hard Disk (HDD) 2.5.1) What is HDD? ◦ Permanent Storage component which use to stores information for the operating system, application & data. ◦ Like an on hand book. ◦ Write/Stored information to be read again at any time. ◦ Size measured in GBs (Gigabyte).1 GBs=one thousand million bytes of information.

2.5 Hard Disk (HDD) 2.5.2) HDD Block Diagram Head Disk Assembly Aluminum Platters to store data Read/Write Head read & write information Actuator Arm which holds the Read/Write Head Actuator which holds the actuator arm Spindle Motor which control the spinning of platters IDE/SATA/SCSI Interface which connect with motherboard Power Connector which connect with motherboard Steel Casing which protect the platters

PCB Assembly Control the movement of head disk assembly

2.5 Hard Disk (HDD) 2.5.2) HDD Block Diagram (continue)

2.5 Hard Disk (HDD) 2.5.3) How HDD Works Data is stored on the surface of a platter in sectors and tracks Tracks are concentric circles, and sectors are pie-shaped wedges on a track Sectors contain fixed number bytes, eg 256 or 512bytes which often group together into clusters

Video Clips Sectors Tracks

2.5 Hard Disk (HDD) 2.5.4) Capacity & Performance of hard disk Maximum Transfer Rate - The data rate is the number of bytes per second that the drive can deliver to the CPU. Rates between 5 and 40 megabytes per second are common.

Spindle Rotation Speed - Hard disk spindle rotation speed - Faster the rotation speed, more data can be written per second

Seek/Access Time - Amount of time between when the CPU requests a file and when the first byte of the file is sent to the CPU. Times between 10 and 20 milliseconds are common.

2.5 Hard Disk (HDD) 2.5.4) Capacity & Performance of hard disk â&#x2014;Ś Capacity - Number of Bytes the hard disk can hold - Capacity = sectors * capacity of sectors * cylinder * Nb Heads. â&#x2014;Ś Revolution Speed - Number of revolutions of the engine of drive of the plates - Express in Turn per Minutes or Revolution Per Minutes (R.P.M) - Common hard disk turn per minutes is 5400, 7200 & 10000 R.P.M

2.5 Hard Disk (HDD) 2.5.5) File System – way of data is stored NSTC (NT file system) - 512MB cluster size (reduce the waste spaces) - 18.5 x 10¹º bytes

FAT 32 (File Allocation Table) - 4KB cluster size - Up to 2TB sizes

FAT 16 - 32KB cluster size - Up to 2GB sizes

2.5 Hard Disk (HDD) 2.5.6) HDD Interface a) IDE (Integrated Drive Electronics) /ATA (Advanced Technology Attachment) - Used in Personal Computers [PCs] as a hard-drive or peripheral bus to interconnect the PC mother board and a hard drive

b) Parallel Bus (PATA) - Maximum 133MB/s data transmission speed - 40 signal (40 pins) using single-ended signaling on an 18â&#x20AC;? cable - Extra 40 ground signal added to reduce noise & filter out outside noise for UDMA

c) Serial ATA (SATA) - 2 pair of signal (7 pins) for sending & receiving <http://www.directron.com/patasata.html> - Low voltage differential signaling - 150MB/s data transmission speed - Better immunity to outside noise

2.5 Hard Disk (HDD) 2.5.6) HDD Interface (Summary of IDE modes)

2.5 Hard Disk (HDD) 2.5.7) eSATA compare with other bus

<http://en.wikipedia.org/wiki/SATA> <http://www.seagate.com/docs/pdf/datasheet/disc/ds_internal_sata.pdf> <http://www.seagate.com/docs/pdf/datasheet/disc/ds_internal_pata.pdf>

2.6 Optical Drive (ODD) 2.6.1) What is Optical Drive? • • • • •

Like a book on a local library Huge information to used/read or write in their book Use a media to read/write in their book Size of media from MB (megabyte) to GB (gigabyte) Refer to lasers which can see, read & write data on optical disk

2.6 Optical Drive (ODD) 2.6.2) Optical Drive basic design

2.6 Optical Drive (ODD) 2.6.2) Optical Drive basic design (continue) a) Laser Diode produce optical lights b) Optical lights passing through a grating, the light diffracts into 3 beams c) Three beams pass through a polarized beam splitter, quarter wave plate & collimator lens to transform laser beams into a collimated beam d) Collimated laser beam then passed through a holographic Fresnel lens. e) The collimated beam then separated into 2 parts & focus to dual focal points, one for reading dvd data & the other for writing cd data. f) the beams then reflect back to the same collimator lens, beam splitter & cylindrical lens & project onto four-quadrant photodiode which output focus error signals (FES) g) FES then to drive the voice coil motor (VCM) to shift the objective lens until focal point is set on the disk surface. h) The pick-up head then transforming the FES into digital signals

2.6 Optical Drive (ODD) 2.6.3) How CD Discs Works a) Understanding of CD: Area of the Disc

PCA – Power Calibration Area (Stores temporary Table Of Content) PMA – Power Memory Area (Test Mark)

2.6 Optical Drive (ODD) 2.6.3) How CD Discs Works (continue) b) Understanding of CD: Material -

Stored up to 74 min of data Maximum amount of data stored in cd is 44,100 samples/channel/second x 2 bytes/sample x 2 channels x 74 minutes x 60 seconds/minute = 783,216,000 bytes

2.6 Optical Drive (ODD) 2.6.3) How CD Discs Works (continue) c) Understanding of CD: The Spiral -

Single spiral of data circling from inner to outer side of the disk

2.6 Optical Drive (ODD) 2.6.3) How CD Discs Works (continue) d) Understanding of CD: Bumps/Pits -

Single spiral of data circling from inner to outer side of the disk

2.6 Optical Drive (ODD) 2.6.4) How DVD Discs Works a) Understanding of DVD: Material -

Stored up to 133 min of data

Maximum amount of data stored in dvd is 8.5GB (DVD+/-R DL)

2.6 Optical Drive (ODD) 2.6.4) How DVD Discs Works (continue) b) Understanding of DVD: The Spiral -

Single spiral of data circling from inner to outer side of the disk

2.6 Optical Drive (ODD) 2.6.4) How DVD Discs Works (continue) c) Understanding of DVD: Bumps/Pits -

Single spiral of data circling from inner to outer side of the disk

2.6 Optical Drive (ODD) 2.6.5) How CD-ROM/DVD-ROM Drives Works a) CD-ROM/DVD-ROM Components -

Finding & reading the data that stored as bumps on CD Fundamental components -

Drive motor â&#x20AC;&#x201C; spin the disc Laser & Lens System focus in on & read the bumps Tracking mechanism moves the laser assembly

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2.6 Optical Drive (ODD) 2.6.5) How CD-ROM/DVD-ROM Drives Works (continue) b) What the CD-ROM/DVD-ROM does â&#x20AC;&#x201C; Laser Focus - Technology which involved in forming the data into understandable & sending to DAC or computer - Fundamental jobs is to focus the laser on the track of bumps

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2.6 Optical Drive (ODD) 2.6.5) How CD-ROM/DVD-ROM Drives Works (continue) c) What the CD-ROM/DVD-ROM does â&#x20AC;&#x201C; Tracking System - To keep the laser beam centered on the data track

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2.6 Optical Drive (ODD) 2.6.6) DVD Disc Capacity

CD & DVD Manufacturing

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2.6 Optical Drive (ODD) 2.6.7) DVD Disc Type

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2.6 Optical Drive (ODD) 2.6.8) DVD Disc Format a) Non-recordable format DVD-ROM Similar to CD Reflective surface is gold or silver Single sided/single layered, double sided/double layer, double sided/single layered & double sided/double layered

DVD-D Self-destructing disposable DVD format

DVD-Plus -

Combine DVD & CD technology

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2.6 Optical Drive (ODD) 2.6.8) DVD Disc Format (continue) b) Recordable format (DVD Forum) DVD-R Record up to 4.7GB Similar fashion to a CD-R disc Can be played by most DVD player

DVD-RW Record up to 4.7GB Similar fashion to a CD-RW disc

DVD-R DL -

Derivate of DVD-R Record up to 8.5GB

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2.6 Optical Drive (ODD) 2.6.8) DVD Discs Format (continue) b) Recordable format (continue) DVD-RAM House in a cartridge Record up to 4.7GB or 9.4GB

c) Recordable format (DVD+RW Alliance) DVD+R Record up to 8.5GB (DL) Similar fashion to a CD-R disc Can be played by most DVD player

DVD+RW -

Record up to 4.7GB Similar fashion to a CD-RW disc Data can be added & removed without erasing the whole disc Treat as large Floppy disk Copyright@2008 Sirnatec IT Centre

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2.6 Optical Drive (ODD) 2.6.8) DVD Discs Format (continue) c) Recordable format (DVD+RW Alliance) DVD+R DL

• • •

Derivate of DVD+R Record up to 17.1GB (DS)

DVD+RW DL

• • • •

Record up to 8.5GB Data can be added & removed without erasing the whole disc Treat as large Floppy disk

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2.6 Optical Drive (ODD) 2.6.9) How CD-Burner Works a) Writing CDs

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2.6 Optical Drive (ODD) 2.6.9) How CD-Burner Works (continue) b) Burning CDs : Laser Assembly

The laser assembly inside a CD burner

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2.6 Optical Drive (ODD) 2.6.9) How CD-Burner Works (continue) c) Burning CDs : Write Laser

The machinery in a CD burner looks pretty much the same as the machinery in any CD player. There is a mechanism that spins the disc and another mechanism that slides the laser assembly.

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2.6 Optical Drive (ODD) 2.6.9) How CD-Burner Works (continue) d) Erasing CDs

In a CD-RW disc, the reflecting lands and non-reflecting bumps of a conventional CD are represented by phase shifts in a special compound. When the compound is in a crystalline state, it is translucent, so light can shine through to the metal layer above and reflect back to the laser assembly. When the compound is melted into an amorphous state, it becomes opaque, making the area non-reflective.

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2.6 Optical Drive (ODD) 2.6.10) Blue-ray Disc Technology a) Media Type - High-density optical disc b) Encoding - MPEG-2,MPEG-4 AVC c) Capacity â&#x20AC;&#x201C; 25GB (single layer) & 50GB (dual layer) d) Read mechanism - 405 nm wavelength blue laser - 1x at 36 Mbit/s - 2x at 72 Mbit/s - 4x at 144 Mbit/s - 6x at 216 Mbit/s - 12x at 432 Mbit/s e) Usage - data storage, high-definition video & PlayStation 3 games

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2.7 Monitor 2.7.1) What is Monitor? - Talking & Writing Devices/Tools (Output Devices) - Send inputs to PC, CPU & produces useful output (Text/Graphics).

Example of LCD Monitor

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2.7 Monitor 2.7.2) Type of Display Technology a) LCD (Liquid Crystal Display) - Used in Digital watches, calculators & etc. - Made out of two layers of very fine glass material called substrate that form a “sandwich” around a thin layer of shaped molecules (liquid crystals) that flow like liquid.

b) CRT (Cathode Ray Tube) - Oldest form of display for PC computer systems.

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2.7 Monitor 2.7.3) What Inside CRT monitor?

(<egative terminal) (Positive terminal)

(Aperture Grill)

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2.7 Monitor 2.7.3) What Inside CRT monitor? (continue) a) Cathode (Electron gun) - Heated Element - Electron gun fires electrons towards front through vacuum which exits in the glass ‘tube’ of the monitor - The “ray” is the stream of electrons that pour off a heat cathode into the vacuum. - The “ray” also correspond to the red, green and blue channel of the display.

b) Anode - Positive terminal which attract the electrons that pouring off from the cathode. - Magnetized according to instructions from the display controller

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2.7 Monitor 2.7.3) What Inside CRT monitor? (continue) c) Shadow Mask/Aperture Grill - Shadow Mask - Shadow mask is a piece of metal with billion of holes which allow different of cathode ray through to hit the phosphor. - Suitable for CAD/CAM drawing application - Aperture Grill - Define the gap through which electrons pass using a mesh of wire. - Use for Flat screen model which produce a clear, undisturbed images & reduce glare from ambient light.

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2.7 Monitor 2.7.4) How CRT Monitor Works

START

Electricity supplied

Anode (C) attracts the electrons & focus the particles into three narrow beams (E)

Cathode/Heat filament (A) heats up

"Ray" of electrons pour off from the cathode into vacuum

The beams strike the Phosphor-coated screen (D) & Shadow Mask/Apertube grill (F)

Phosphors emit red, green & blue light used in a color monitor

END

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2.7 Monitor 2.7.5) How LCD Monitor works?

a) Basic principles of LCD panel: 1) Alignment of liquid crystal molecules can be controlled by - fine grooves etched into a glass plate - electric current/voltage 2) Light follows liquid crystal molecules 3) Polarizing filters block light

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2.7 Monitor 2.7.5) How LCD Monitor works? (continue) b) What is a Liquid Crystal? - Physical properties of solid & liquid. - As a liquid they are able to flow over & around small grooves & can change their position depending on applied voltage.

c) Aligning Liquid Crystal Molecules & Rotating Light - Molecules are basically a rectangular shape which align in random tilt with their long axes parallel. - When contact with grooved surfaces, the liquid crystal molecules easily orient to be parallel to the grooves.

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2.7 Monitor 2.7.5) How LCD Monitor works? (continue) c) Aligning Liquid Crystal Molecules & Rotating Light (continue) - To make a basic â&#x20AC;&#x153;twistedâ&#x20AC;? LC panel, liquid crystal is sandwiched between two transparent plates. - Each plate contains very fine grooves, with grooves in each panel placed exactly perpendicular. - Follow the direction of the molecules as the light passed through the liquid crystals.

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2.7 Monitor 2.7.5) How LCD Monitor works? (continue) c) Aligning Liquid Crystal Molecules & Rotating Light (continue) - Liquid Crystal Molecules can be rearranged by applying an external voltage. - The liquid crystal molecules begin to rearrange themselves with the electric field as the voltage applied.

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2.7 Monitor 2.7.5) How LCD Monitor works? (continue) d) Blocking Light with Polarizing Filters (continue) - Polarizing filter is a set of extremely closely spaced parallel lines. - This lines only allow the light waves that are parallel to them to pass through. Light from other direction are blocked.

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2.7 Monitor 2.7.5) How LCD Monitor works? (continue) e) Controlling Light with an LCD Panel - Light can be rotated by using the properties of liquid crystal. - Figure below illustrations the polarizing filter are oriented perpendicular, thus prevent incoming light from getting through. the the

- Figure left illustrated : Light waves with â&#x20AC;&#x153;Aâ&#x20AC;? orientation pass through 1st(top) filter. These light waves are then rotated 90o by liquid crystal in twisted structure arrangement.

the

- Figure right illustrated: A voltage is applied to the liquid crystal, causing

molecules to re-align themselves vertically causing no light passes through the liquid crystal panel. Copyright@2008 Sirnatec IT Centre

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2.7 Monitor 2.7.6) Performance Measurements a) Monitor Size & Viewable Area: measured diagonally from one corner of the glass to the opposite. CRT – actual size & viewable screen size LCD – actual size/viewable screen size b) Resolution: number of horizontal & vertical pixels that the monitor contain (without scaling the screen contents up or down). Here are some of the common resolutions found in LCD monitor, 14-15": 1024x768 (XGA) 17-19": 1280x1024 (SXGA) 20"+: 1600x1200 (UXGA) 19” (Widescreen): 1440x900 (WXGA+) 20” (Widescreen): 1680x1050 (WSXGA+) 24” (Widescreen): 1920x1200 (WUXGA) 30” (Widescreen): 2560x1600 Copyright@2008 Sirnatec IT Centre

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2.7 Monitor 2.7.6) Performance Measurements (continue) Here are some of the common resolutions found in CRT monitor, SVGA : 800x600 XGA : 1024x768 SXGA : 1280x1024 UXGA : 1600x1200 c) Aspect Ratio: ratio between the horizontal dimension & the vertical dimension. Common aspect ratios are 4:3 (1.333) & 5:4(1.25). Resolutions with a 4:3 aspect ratio: 800 x 600 1024 x 768 1152 x 864 1600 x 1200 Resolutions with a 5:4 aspect ratio: 1280 x 1024 1600 x 1280 Copyright@2008 Sirnatec IT Centre

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2.7 Monitor 2.7.6) Performance Measurements (continue) d) Dot pitch: measure of the amount of space between each pixel. (Note: the smaller the dot pitch, the sharper the image) e) Brightness: determined by the intensity & quality of the backlighting. Usually measured in luminance (candelas per square meter). f) Color depth: the number of colors that can represented on a display without dithering (full color depth for CRT able to provide 16,770,000 colors while for LCD only able to provide 2,600,000 colors) g) Contrast: measure of the range between the lightest tones & the darkest tones. A higher contrast ratio makes the information more readable. h) Viewing angle: determines how far above,below,or either side of the display a person can view.

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2.7 Monitor 2.7.6) Performance Measurements (continue) i) Pixel response rate/Response Time: the time it takes for a pixel to response to voltage (to be turned â&#x20AC;&#x153;onâ&#x20AC;?) & then back to its normal state. It measured in milliseconds or microseconds (the minimum response time should be at least 25ms & 17ms is recommended). j) Vertical Refresh Rate: The number of times a screen can be completely redrawn/re-painted in a second. The refresh rate of 75Hz is sufficient for LCD monitor

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2.7 Monitor 2.7.7) Comparison of LCD & CRT Monitor

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2.7 Monitor 2.7.8) Pros & Cons of CRT & LCD Monitors a) CRT Monitors Pros:

Multisync Capable High Refresh Rates Color Clarity & Depth

Cons:

Very Heavy & large Use Large Amount of Energy Generate Excess Heat

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2.7 Monitor 2.7.8) Pros & Cons of CRT & LCD Monitors (continue) b) LCD Monitors Pros:

Smaller and Lighter Energy Efficient Causes Less Eye Fatigue

Cons:

Blurry images outside Native Resolution Motion Blur on Fast Moving Images Come Models Have Reduced Color Clarity

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2.8 Modem 2.8.1) What is Modem? - Peripheral devices which allows 2 computers to communicate over standard phone lines (Communication Platform) - The word “modem” stand for “modulator-demodulator” - The sending modem modulated the digital data into analog signal & the receiving modem demodulates back the analog signal into digital data. - Download speed up to 3Mbps - Upload speed up to 1Mbps

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2.8 Modem 2.8.2) What Inside Modem? a) Tuner - receives the modulated digital signals from cable outlet & passes to the demodulator - Splitter to separate the internet data from normal TV programming - Diplexer allow to make use of one set frequency for downstream & another for upstream data

b) Demodulator - Quadrature amplitude modulation (QAM) demodulator takes a radiofrequency signal that had information encoded in it by varying both amplitude & phase of the wave & turn into simple signal that can be processed by A/D converter. - A/D converter turn into series of digital 1s & 0s. - Error correction module then check the received information against a known standard

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2.8 Modem 2.8.3) Modem Technology a) Smart Modem - V.90 bits standard operating at 56kbps, upload speed up to 33.6kbps - V.92 bits standard operating at 56kbps, upload speed up to 48kbps - able to put dial-up internet connection on-hold when answering a call - ability to “quick connect” to one’s ISP

b) DSL modem (broadband) - Stand for “Digital Subscriber Line” which allow high speed internet access to home & small internet business over existing telephone wires. - Download speed up to 8Mbps, upload speed up to 1Mbps - Capable of modulating/demodulating hundreds of channel simultaneously - Include function of Routers

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2.8 Modem 2.8.4) DSL Technology - Stand for â&#x20AC;&#x153;Digital Subscriber Lineâ&#x20AC;? - Convert s existing copper telephone lines into high speed data communication. - Transmit through downstream & upstream bandwidth. - Operate over a single twisted copper pair of wires.

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2.8 Modem 2.8.5) Advantage & Disadvantage of DSL • Advantage of DSL • • • •

•

You can leave your Internet connection open and still use the phone line for voice calls. The speed is much higher than a regular modem DSL doesn't necessarily require new wiring; it can use the phone line you already have. The company that offers DSL will usually provide the modem as part of the installation.

Disadvantage of DSL •

• •

A DSL connection works better when you are closer to the provider's central office. The farther away you get from the central office, the weaker the signal becomes. The connection is faster for receiving data than it is for sending data over the Internet. The service is not available everywhere.

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2.8 Modem 2.8.6) DSL Equipment â&#x20AC;˘

Transceiver - At the customer's location, there is a DSL transceiver, which may also provide other services.

â&#x20AC;˘

DSL access multiplexer (DSLAM) - The DSL service provider has a DSLAM to receive customer connections.

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2.8 Modem 2.8.7) DSL Type •

Asymmetric DSL (ADSL) - It is called "asymmetric" because the download speed is greater than the upload speed. ADSL works this way because most Internet users look at, or download, much more information than they send, or upload.

•

High bit-rate DSL (HDSL) - Providing transfer rates comparable to a T1 line (about 1.5 Mbps), HDSL receives and sends data at the same speed, but it requires two lines that are separate from your normal phone line.

•

ISDN DSL (ISDL) - Geared primarily toward existing users of Integrated Services Digital Network (ISDN), ISDL is slower than most other forms of DSL, operating at fixed rate of 144 Kbps in both directions. The advantage for ISDN customers is that they can use their existing equipment, but the actual speed gain is typically only 16 Kbps (ISDN runs at 128 Kbps).

•

Very high bit-rate DSL (VDSL) - An extremely fast connection, VDSL is asymmetric, but only works over a short distance using standard copper phone wiring.

•

Multirate Symmetric DSL (MSDSL) - This is Symmetric DSL that is capable of more than one transfer rate. The transfer rate is set by the service provider, typically based on the service (price) level.

•

Rate Adaptive DSL (RADSL) - This is a popular variation of ADSL that allows the modem to adjust the speed of the connection depending on the length and quality of the line. Copyright@2008 Sirnatec IT Centre

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2.8 Modem 2.8.7) DSL Type (continue) •

Symmetric DSL (SDSL) - Like HDSL, this version receives and sends data at the same speed. While SDSL also requires a separate line from your phone, it uses only a single line instead of the two used by HDSL.

•

Voice-over DSL (VoDSL) - A type of IP telephony, VoDSL allows multiple phone lines to be combined into a single phone line that also includes data-transmission capabilities. DSL Type

Max. Send Speed

Max. Receive Speed

Max. Distance

Lines Required

Phone Support

ADSL

800 Kbps

8 Mbps

18,000 ft (5,500 m)

Yes

HDSL

1.54 Mbps

12,000 ft (3,650 m)

IDSL

144 Kbps

35,000 ft (10,700 m)

MSDSL

2 Mbps

29,000 ft (8,800 m)

RADSL

1 Mbps

7 Mbps

18,000 ft (5,500 m)

Yes

SDSL

2.3 Mbps

22,000 ft (6,700 m)

VDSL

16 Mbps

52 Mbps

4,000 ft (1,200 m)

Yes

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2.9 Local Area Network (LAN) 2.9.1) Network Overview •

Network - a group of computers connected together in a way that allows information to be exchanged between the computers.

•

Node - A node is anything that is connected to the network. While a node is typically a computer, it can also be something like a printer or CD-ROM tower

•

Segment - A segment is any portion of a network that is separated, by a switch, bridge or router, from other parts of the network

•

Backbone - The backbone is the main cabling of a network that all of the segments connect to. Typically, the backbone is capable of carrying more information than the individual segments. For example, each segment may have a transfer rate of 10 Mbps (megabits per second), while the backbone may operate at 100 Mbps

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2.9 Local Area Network (LAN) 2.9.1) Network Overview •

Topology - Topology is the way that each node is physically connected to the network

•

Local Area Network (LAN) - A LAN is a network of computers that are in the same general physical location, usually within a building or a campus. If the computers are far apart (such as across town or in different cities), then a Wide Area Network (WAN) is typically used

•

Network Interface Card (NIC) - Every computer (and most other devices) is connected to a network through an NIC. In most desktop computers, this is an Ethernet card (normally 10 or 100 Mbps) that is plugged into a slot on the computer's motherboard

•

Media Access Control (MAC) address - This is the physical address of any device -- such as the NIC in a computer -- on the network. The MAC address, which is made up of two equal parts, is 6 bytes long. The first 3 bytes identify the company that made the NIC. The second 3 bytes are the serial number of the NIC itself

•

Unicast - A unicast is a transmission from one node addressed specifically to another node

•

Multicast - In a multicast, a node sends a packet addressed to a special group address. Devices that are interested in this group register to receive packets addressed to the group. An example might be a Cisco router sending out an update to all of the other Cisco routers

•

Broadcast - In a broadcast, a node sends out a packet that is intended for transmission to all other nodes on the network

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2.9 Local Area Network (LAN) 2.9.2) LAN Component •

Network Interface Card (NIC)

•

Writing Hub

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2.9 Local Area Network (LAN) 2.9.2) LAN Component •

Cables or Transmission Media

•

Network Cabling •

Coaxial cable

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2.9 Local Area Network (LAN) 2.9.2) LAN Component •

Cables or Transmission Media •

Network Cabling (continue) •

Twisted-pair (or copper)

•

Fiber-optic cable

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2.9 Local Area Network (LAN) 2.9.3) Bandwidth â&#x20AC;˘ â&#x20AC;˘

A rate of data transfer, or bit rate, measured in bits per second Difference between the highest and the lowest frequencies available for network signals. This quantity is measured in Megahertz (MHz)

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2.9 Local Area Network (LAN) 2.9.3) LAN Topology â&#x20AC;˘

Bus - Each node is daisy-chained (connected one right after the other) along the same backbone, similar to Christmas lights. Information sent from a node travels along the backbone until it reaches its destination node. Each end of a bus network must be terminated with a resistor to keep the signal that is sent by a node across the network from bouncing back when it reaches the end of the cable.

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2.9 Local Area Network (LAN) 2.9.3) LAN Topology (continue) â&#x20AC;˘

Ring - Like a bus network, rings have the nodes daisy-chained. The difference is that the end of the network comes back around to the first node, creating a complete circuit. In a ring network, each node takes a turn sending and receiving information through the use of a token. The token, along with any data, is sent from the first node to the second node, which extracts the data addressed to it and adds any data it wishes to send. Then, the second node passes the token and data to the third node, and so on until it comes back around to the first node again. Only the node with the token is allowed to send data. All other nodes must wait for the token to come to them.

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2.9 Local Area Network (LAN) 2.9.3) LAN Topology (continue) â&#x20AC;˘

Star - In a star network, each node is connected to a central device called a hub. The hub takes a signal that comes from any node and passes it along to all the other nodes in the network. A hub does not perform any type of filtering or routing of the data. It is simply a junction that joins all the different nodes together.

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2.9 Local Area Network (LAN) 2.9.3) LAN Topology (continue) â&#x20AC;˘

Star bus - Probably the most common network topology in use today, star bus combines elements of the star and bus topologies to create a versatile network environment. Nodes in particular areas are connected to hubs (creating stars), and the hubs are connected together along the network backbone (like a bus network). Quite often, stars are nested within stars

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2.9 Local Area Network (LAN) 2.9.4) LAN Devices •

Hub

•

Bridge

•

Switches

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2.9 Local Area Network (LAN) 2.9.4) LAN Devices (continue) • Router •A device that forwards data packets along networks. •A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP’s network. •Routers are located at gateways, the places where two or more networks connect. •Routers use headers and forwarding tables to determine the best path for forwarding the packets, and they use protocols such as ICMP to communicate with each other and configure the best route between any two hosts.

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2.9 Local Area Network (LAN) 2.9.5) LAN Technology • Ethernet •

• • •

•

Ethernet is the most popular physical layer LAN technology because it strikes a good balance between speed, cost, and ease of installation Supports virtually all network protocols Ethernet is standardized as IEEE 802.3 which raises speed from 10 Mbps to 100 Mbps Gigabit Ethernet is an extension of IEEE 802.3 which increases speeds to 1000 Mbps, or 1 Gbps

Ethernet Protocol Name Copyright@2008 Sirnatec IT Centre

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2.9 Local Area Network (LAN) 2.9.5) LAN Technology â&#x20AC;˘ Ethernet Protocol

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2.9 Local Area Network (LAN) 2.9.6) Home Networking â&#x20AC;˘ â&#x20AC;˘

Residential local area network which used to connect multiple devices within the home Connect 2 or more PCs for sharing files, printers, and a single connection to the Internet (usually broadband Internet through a cable or DSL provider)

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2.9 Local Area Network (LAN) 2.9.7) Home Networking Devices â&#x20AC;˘

A broadband modem for connection to the internet (either a DSL modem using the phone line, or cable modem using the cable internet connection)

DSL Modem

Cable Modem

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2.9 Local Area Network (LAN) 2.9.7) Home Networking Devices â&#x20AC;˘

(continue)

A residential gateway/router connected between the broadband modem and the rest of the network. This enables multiple devices to connect to the internet simultaneously. Residential gateways, hubs/switches, DSL modems, and wireless access points are often combined.

Wired Router

Wired Router Layout Wireless Router Layout

Wireless Router

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2.9 Local Area Network (LAN) 2.9.7) Home Networking Devices •

(continue)

A wireless access point, usually implemented as a feature rather than a separate box, for connecting wireless devices

New Wireless Network Setup – Wireless Router

Existing Wired Router – Wireless Access Point Copyright@2008 Sirnatec IT Centre

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2.9 Local Area Network (LAN) 2.9.7) Home Networking Devices (continue) â&#x20AC;˘

A Physical layout of Streamyx Broadband Services

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2.10 Graphic Card 2.10.1) What is Graphic Card? - Output Devices - As a “Translator” which convert binary data from CPU into picture - Consists of GPU, Memory, Motherboard & Monitor connection

DVI Port S-Video (TV Out) VGA Port

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2.10 Graphic Card 2.10.2) What inside Graphic Card? a) Print Circuit Board i) Motherboard - Houses GPU & RAM - BIOS (input/output system) stores the cardâ&#x20AC;&#x2122;s setting & perform diagnostics.

ii) GPU (Graphics Processor Unit)

- Perform complex mathematical & geometric calculations. - Usually cover with heat sink due to a lot of heat generated. - ATI & nVidia cover up majority of GPUs market. Copyright@2008 Sirnatec IT Centre

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2.10 Graphic Card 2.10.2) What inside Graphic Card? (continue) a) Print Circuit Board (continue) iii) Video BIOS (Firmware) - Basic program that governs video card operation. - Contain information on memory timing, operation speeds & voltages iv) Video Memory (VRAM)

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2.10 Graphic Card 2.10.2) What inside Graphic Card? (continue) a) Print Circuit Board (continue) iv) Video Memory (VRAM) (continue) - Act as frame buffer which hold information until suitable time to display. - Capacity from 32MB to 1024MB - Base on DDR & GDDR Technology - Memory Clock in between 400 MHz and 1.6 GHz. - Operate very high speeds & can read & write at the same time. - Connect to DAC (digital-to-anolog converter) which translate the image into anolog signal that monitor can use.

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2.10 Graphic Card 2.10.2) What inside Graphic Card? (continue) b) Interface Connector - VGA (Video Graphic Array) Outputs (D-Sub)

- DVI (Digital Visual Interface) Output

- Composite Video

- S-Video

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2.10 Graphic Card 2.10.2) What inside Graphic Card? (continue) b) Interface Connector (continue) - Component Video (Y, Pb, Pr)

- HDMI (High Definition Multimedia Interface) - Support both Video & Audio information in same cable. - Created for TV/Movie application

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2.10 Graphic Card 2.10.3) Graphic Card Interface a) PCI (Peripheral Component Interconnect)

Graphic Card Connector

Graphic Card Motherboardâ&#x20AC;&#x2122;s Connector

- Maximum 65 bit wide bus that run at 66 MHz - Bandwidth of 133 MB/s

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2.10 Graphic Card 2.10.3) Graphic Card Interface (continue) b) AGP (Accelerated Graphic Port)

- Based on PCI re. 2.1 specification - Directly read/write capabilities with system memory - Bandwidth/Data Rate up to 2.1 GB/s / AGP 8x Version AGP 1x AGP 2x AGP 4x AGP 8x

Operate Channel Frequrency 32-bit 66 MHz 32-bit 133 MHz 32-bit 266 MHz 32-bit 533 MHz

Data Rate 266 MB/s 533 MB/s 1066 MB/s 2133 MB/s

Signaling Voltage 3.3 V 3.3 V 1.5 V 0.8 V

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2.10 Graphic Card 2.10.3) Graphic Card Interface (continue) c) PCI-E/PCIe (PCI Express) - Maximum Bandwidth of 80 Gb/s for x16 lanes.

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2.10 Graphic Card 2.10.3) Graphic Card Interface (continue) d) PCIe Lanes

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2.10 Graphic Card 2.10.4) Type of Graphic Card a) NVIDIA (Geforce Series) i) GeForce 8 Series ii) Geforce 7 Series iii) Geforce 6 Series GPUs b) NVIDIA (Quadro Series) i) FX 4500 SDI ii) FX 4000 SDI iii) FX 4500 c) ATI Radeon (R300 PCIe Series) i) Radeon Xpress 200 IGP ii) Radeon Xpress 1100 IGP iii) Radeon Xpress 1150 IGP iv) Radeon Xpress 300 SE

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2.10 Graphic Card 2.10.4) Type of Graphic Card

(continue)

d) ATI Radeon (R400 PCIe Series) i) Radeon Xpress 1250 IGP ii) Radeon Xpress 1270 IGP iii) Radeon Xpress 1250 IGP e) ATI Radeon (R500 PCIe Series) i) Radeon Xpress 1300 ii) Radeon Xpress 1550 iii) Radeon Xpress 1600 f) ATI Radeon (R600 PCIe Series) i) Radeon 780 IGP ii) Radeon HD 2350 iii) Radeon HD 2400 iv) Radeon HD 2600 v) Radeon HD 2900

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2.11 Keyboard 2.11.1) What is Keyboard - Like an eyes & ears - Use to control computers - Series of switches connected to microprocessor to initiates response of changes - A typing or input devices - To type a document, keystroke shortcuts, access menu, play games - Part of a laptop or attach to the computer

2.11.2) Types of Keyboard - 101-key Enhanced keyboard - 104-key Windows keyboard - 82-key apple standard keyboard - 108-key Apple Extended keyboard

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2.11 Keyboard 2.11.3) Common Keyboard Keys i) Typing keys - letters of an alphabet - same pattern layout (QWERT) as typewriters - others layout is Dvorak, ABCDE, XPeRT, QWERTZ & AZERTY ii) Numeric keypad - Data entry (0 to 9) - 17 keys - Same configuration as adding machines & calculators

iii) Function key - Arranged in a line across the top of keyboard - F1 to F12

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2.11 Keyboard 2.11.3) Common Keyboard Keys

(continue)

iv) Control key - Arrow keys - Home, End - Insert, Delete - Page Up, Page Down - Control (Ctrl), Alternate (Alt) - Escape (Esc) - Windows/Start

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2.11 Keyboard 2.11.4) What inside Keyboard? i) Microprocessor & controller circuitry

ii) Key Matrix - Grid of circuits underneath the keys - Press a key, it presses a switch, allowing current to through. - Mechanical action of the switch causes vibration, called bounce. - Character map is a comparison chart or lookup table

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2.11 Keyboard 2.11.5) Keyboard Switches i) Dome-switch

bubble

- Also called direct-switch keyboards - Kind of hybrid of membrane & mechanical keyboard - Bring two circuit board trances together under a rubber â&#x20AC;&#x153;domeâ&#x20AC;? or

ii) Scissor-switch - The keys are attached to the keyboard via two plastic piece interlock like a scissor. - Mainly used in laptop/notebook.

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2.11 Keyboard 2.11.5) Keyboard Switches

(continue)

iii) Capacitive - Pressing the key changes the capacitance of a pattern printed on a

board - Resist wear, foreign objects & dirt

iv) Mechanical-switch - Use real switches, one under each key. - Mainly used in Apple Extended II.

v) Membrane - Flat - Often found on microwave ovens/photocopies - Consists of 3 layers 1) Top layer has a label printed on front & conductive stripes printed on the back. front

2) Spacer layer, holds the front & back layer apart 3) Back layer has conductive stripes printed perpendicularly to those of the layer

vi) Roll-up

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2.11 Keyboard 2.11.6) Connection Types i) PS/2

ii) USB (Universal Serial Bus) iii) Wireless - Infrared (IR), radio frequency (RF) or Bluetooth connections. - Require a receiver to be plug into USB port. - AC power connection or batteries for power.

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2.12 Mouse 2.12.1) What is Mouse? - Input or Pointing Devices - To control a cursor to manipulate data without complicated command

2.12.2) What inside Mouse? Electrical Controller (DSP)

Mechanical Portion

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2.12 Mouse 2.12.3) Type of Mouse a) Mechanical Mouse - Set on flat surface - Distance & speed of the rollers determine how far the cursor moves on the screen

b) Optical Mouse - Light-emitting diode (LED) & photodiodes to detect the movement relative to underlying surface.

- Benefit of Optical Mouse over Mechanical Mouse i) No moving parts means less wear and a lower chance of failure. ii) There's no way for dirt to get inside the mouse and interfere with the tracking sensors. iii) Increased tracking resolution means smoother response. iv) They don't require a special surface, such as a mouse pad. Copyright@2008 Sirnatec IT Centre

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2.12 Mouse 2.12.3) Type of Mouse (continue) c) Wireless Mouse - Radio frequency (RF) technology for communication - Two main components: a transmitter & receiver - Benefit of Wireless Mouse i) RF transmitters require low power and can run on batteries ii) RF components are inexpensive RF components are light weight

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2.12 Mouse 2.12.4) How a Mechanical Mouse Works i) Moving the mouse turns the ball. ii) X and Y rollers grip the ball and transfer movement. iii) Optical encoding disks include light holes. iv) Infrared LEDs shine through the disks. v) Sensors gather light pulses to convert to X & Y velocities

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2.12 Mouse 2.12.5) How an Optical Mouse Works i) The CMOS sensor sends each image to a digital signal processor (DSP) for analysis. ii) The DSP detects patterns in the images and examines how the patterns have moved since the previous image. iii) Based on the change in patterns over a sequence of images, the DSP determines how far the mouse has moved and sends the corresponding coordinates to the computer. iv) The computer moves the cursor on the screen based on the coordinates received from the mouse. This happens hundreds of times each second, making the cursor appear to move very smoothly

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2.12 Mouse 2.12.6) How an Wireless Mouse Works i) The transmitter is housed in the mouse. It sends an electromagnetic (radio) signal that encodes the information about the mouse's movements and the buttons you click. ii) The receiver, which is connected to your computer, accepts the signal, decodes it and passes it on to the mouse driver software and your computer's operating system. iii) The receiver can be a separate device that plugs into your computer, a special card that you place in an expansion slot, or a built-in component.

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2.12 Mouse 2.12.7) Data Interface - USB

- PS/2

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2.13 Power Supply 2.13.1) What is Power Supply • • • • • • •

Supplies power to a computer Also call “Switching Power Supplier” Use switcher technology to convert the alternating current (AC) to direct current (DC) Typical voltages supplied are 3.3 volts, 5 volts & 12 volts 3.3 & 5 volts used by digital circuits 12 volt used t run motors in disk drives & fans Main specification of power supply is watts (voltage x current)

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2.13 Power Supply 2.13.2) Basic Component of PSU •

Cover - square metal box. Dimensions of an ATX PSU are usually 150 x 86 x 140mm

•

On-off Switch - manual switch on the back to ensure that the computer is truly off and no power is being sent to the components

•

Fan - 80mm or 120mm or even a 140mm fan to cool it’s components and exhaust the heat out the back

Power Connectors

On-off Switch

Cover Fan

Power Cord Port

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2.13 Power Supply 2.13.2) Basic Component of PSU •

(continue)

Main Power Connectors (also called 20- or 24-pin ATX connector) - the

connector that goes to the motherboard to provide the power.

•

ATX12V 4-pin power connector (also called “CPU power connector”) - a 2nd connector that goes to the motherboard that brings extra power to the CPU socket area

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2.13 Power Supply 2.13.2) Basic Component of PSU

(continue)

â&#x20AC;˘

4-pin peripheral power connectors (also known as Molex connectors) which for various drives e.g. Hard disk, CD/DVD-ROM

â&#x20AC;˘

Serial ATA (SATA) power connectors - a 15-pin connector for components which use SATA power plugs e.g. SATA Hard disks

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2.13 Power Supply 2.13.2) Basic Component of PSU •

6-pin & 8-pin PCI-E power connector

8-pin PCI-E Power Connector

•

(continue)

6-pin PCI-E Power Connector

Power Rating for PCI-E Graphic Card

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2.13 Power Supply 2.13.3) How Power Supplies Work â&#x20AC;˘

Used Transformers & Capacitors to convert Line Voltage at 120 volts & 60 herts into 5 volts & 12 volts DC

Transformer

Capacitors

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2.13 Power Supply 2.13.4) Power Supply Terms 1) Watt - The accepted market rating for power supplies - Watts = Volts(v) x Amps(A) - This formula is important to calculate the wattage on each rail

2) Rails - Every power supply has many rails. Each rail is rated for a specific voltage, and will always carry that voltage no matter how many devices are connected to it - However, each rail has an AMPERE RATING (A). The more devices you connect to each rail, the lower the available amperage to the rest of your computer system will be on that specific rail.

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2.13 Power Supply 2.13.5) Power Supplies Form Factor

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2.13 Power Supply 2.13.6) How to read PSU Specification • • • •

1st Row - shows your AC input (your wall socket voltage i.e. 240v for Malaysia) 2nd Row - shows the DC output to all the rails (i.e. +3.3v, +5v, dual 12v rail (+12V1 & +12V2), -12v, +5vsb) rd 3 Row - shows the Amperage (A) for each rail 4th Row - shows the maximum wattage for the rails

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2.12 Power Supply 2.12.6) How to read PSU Specification

(continue)

- Output Power Calculation

ATX/NLX, SFX & WTX form factor

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2.13 Power Supply 2.13.7) How much Power do you need?

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2.14 Printer 2.14 14..1 Printer Features I) What is Printer? - Devices that print text or graphics on physical print media such as paper

II) Printing Speed - Speed is measured in ppm (pages per minute)

III) Printing Paper Type

Continuous-Form Paper (donâ&#x20AC;&#x2122;t need to load in paper often) Single Sheet (can change to special paper easily, like letterhead or envelopes)

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2.14 Printer 2.14 14..1 Printer Features (continue) iv) Printing Quality - Measure in print resolution or dot per inch(dpi) - 1200 to 2400 dpi printers for graphics used while 600 dpi for normal printing

v) Printing Mode (what we saw from paper after printing) - Typeface - Styles (Bold, italic, underlined..) - Size (measured in points, one point = 1/72 inch) - Font - Color - Graphics

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2.14 Printer 2.14.2) Inject Printer â&#x20AC;˘

Introduction to Inject Printer paper -

Image is created by placing extremely small droplets of ink onto Dots are extremely small (between 50 and 60 microns in diameter) Resolution up to 1440x720 dots per inch (dpi) Different colors combined to create photo-quality images

- Use Serial Printing Process

- Also use Line inject printer printing process

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2.14 Printer 2.14.2) Inject Printer â&#x20AC;˘

Inject Printer Features - Quiet operation - Capability to produce color images with photographic quality - Expensive to maintenance compare with laser printing

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2.14 Printer 2.14.2) Inject Printer What inside Inject Printer?

•

Print Head Assembly that

i) Print Head – the core of inject printer which contains a series of nozzles are used to spray drops of ink. ii) Ink cartridges – come in various combinations (color & black in single & separated cartridges)

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2.14 Printer 2.14.2) Inject Printer What inside Inject Printer?

â&#x20AC;˘

Print Head Assembly (continue) &

iii) Print Head Stepper Motor â&#x20AC;&#x201C; moves the print head assembly (print head ink cartridges) back & forth across the paper.

Stepper motors control the movement of most parts of an inject printer

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2.14 Printer 2.14.2) Inject Printer •

What inside Inject Printer? Print Head Assembly (continue) iv) Belt – attach the print head assembly to the stepper motor. v) Stabilizer bar – to ensure that movement is precise & controlled.

Stabilizer bar & Belt

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2.14 Printer 2.14.2) Inject Printer •

What inside Inject Printer? Paper Feed Assembly

i) Paper Tray/Feeder – to load the paper into. ii) Rollers – pull the papers in from the tray or feeder. iii) Paper feed stepper motor – supply powers the rollers to move the paper the exact increment needed. iv) Power supply – supply power to the printer

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2.14 Printer 2.14.2) Inject Printer â&#x20AC;˘

What inside Inject Printer? Power Supply - To supply power to the printer.

Control Circuitry - To control mechanical aspects of operation. - To decode information send from computer.

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2.14 Printer 2.14.3) Laser Printer - Produces high quality text & graphics on printing media such as paper - Images is produced by direct scanning of a laser beam across the photoreceptor

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2.14 Printer 2.14.3) Laser Printer •

What inside Laser Printer - Static electricity - As temporary “glue” - Core component is photoreceptor

The path of a piece of paper through a laser printer

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

How Laser Printer Works - Roster image processing

printed.

- Each horizontal strip of dots across the page is known as Raster/scan line . - Raster Image Processor (RIP) is use to create an image to be - Source material may encoded in Adobe PostScript(PS)/Printer Command Language(PCL)/Unformatted text-only data. - Raster Image Memory generate bit map of final pages by RIP.

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

How Laser Printer Works (continue) - Charging - Corona wire projects an electrostatic charge onto photoreceptor (photosensitive drum or belt).

Applying a negative charge to the photosensitive drum

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2.14 Printer 2.14.3) Laser Printer •

How Laser Printer Works (continue) - Writing - Laser is reflected onto photoreceptor (discharge certain points). - The laser “draws” the letters & images to be printed as a pattern

of electrical charges (electrostatic image)

How the bitmap is written to the photosensitive drum Copyright@2008 Sirnatec IT Centre

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

How Laser Printer Works (continue) - Developing - Done by spreading positive charges toner, fine powder over the surface, making

the latent image visible.

- Transferring - Photoreceptor is pressed over paper, transferring the images. - Discharged by the detac corona wire immediately after picking up the toner. transfer

Note: before the paper rolls under the drum, it is given a negative charge by the corona wire. This charge is stronger than negative charge of the electrostatic image, so the paper can pull the toner powder away

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

How Laser Printer Works (continue) - Fusing - Paper passes through rollers in the fuser assembly where heat and pressure bond the plastic powder to the paper.

- Cleaning - Electrically neutral soft plastic blade cleans excess toner from the photoreceptor and deposits into a waste reservoir

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

Printer Controller: The Conversation - Receive, process & transfer page data - Communicate through parallel/serial/USB port

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2.14 Printer 2.14.3) Laser Printer Printer Controller: The Language

â&#x20AC;˘

- Communicate between printer controller & host computer - Common language is Printer Command Language (PCL) & Postscript. Describe the page is vector form.

Printer Controller: Setting up the Page

â&#x20AC;˘

- Raster Image Processor (RIP) takes the arranges text/graphics in tiny

whole piece/piece by piece & break down into an array of dots.

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

Printer Controller: Laser Assembly - A laser - A movable mirror - A lens

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

Scanning Process

Latent Image Creation

LED Scanning Process

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2.14 Printer 2.14.3) Laser Printer â&#x20AC;˘

Printer Features

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2.15 Speaker 2.15.1) What is Speaker - Output devices that able to produce sound for a given instruction.

2.15.2) Type of Speaker a) PC Speaker low-

- Also known as Multimedia Speakers commonly come with a power internal amplifier. - Standard audio connection is a 3.5mm stereo jack plug (green).

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2.15 Speaker 2.15.2) Type of Speaker (continue) b) Loudspeakers - Complete speaker system consists of an enclosure.

219

2.15 Speaker 2.15.2) Type of Speaker (continue) c) Sound card audio

- Computer expansion card that facilitates the input & output of signals to/from a computer.

220

2.15 Speaker 2.15.2) Type of Speaker d) Headphone - Also known as earphones, headsets are a pair of small loudspeaker with a way of holding them close to ears.

221

2.15 Speaker 2.15.2) Type of Speaker e) Microphone - Also known as mike or mic is an acoustic-to-electric transducer or sensor that converts sound into an electrical signal.

222

2.15 Speaker 2.15.3) Common features of PC Speaker a) LED power indicator b) 3.5mm (1/8-inch) headphone jack c) Controls for volume, bass & treble d) A remote volume control (a)

2.5mm mono,3.5mm mono and stereo & 6.3mm stereo jack plugs

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2.15 Speaker 2.15.4) Sound Basic - Object produces sound when it vibrates in the air. - Example of how to produces a sound (Bell)

224

2.15 Speaker 2.15.5) Inside Speaker - Speaker is the final translation machine which translate electrical signal back into physical vibrations to create sound waves.

225

2.15 Speaker 2.14.5) Inside Speaker

(continue)

I) Cone - made of paper/plastic/metal attached on wide end to the suspension. the

II) Suspension/surround - allows the cone to move, attached to metal frame, called the basket. III) Voice coil - connected from the cone.

back

IV) Spider - hold the coil in position, but allow to move freely & forth.

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2.15 Speaker 2.15.6) How Sound is produced

When the electrical current flowing through the voice coil changes direction, the coil's polar orientation reverses. This changes the magnetic forces between the voice coil and the permanent magnet, moving the coil and attached diaphragm back and forth.

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2.15 Speaker 2.15.7) Type of Driver I) Woofers - biggest drivers which are use to produce low frequency sounds.

II) Tweeters â&#x20AC;&#x201C; to produce high frequency sounds

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2.15 Speaker 2.15.7) Type of Driver

(continue)

III) Midrange â&#x20AC;&#x201C; produce a range of frequency in the middle of the sound spectrum

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2.15 Speaker 2.15.8) Sealed Speaker Enclosures III) Midrange â&#x20AC;&#x201C; produce a range of frequency in the middle of the sound spectrum

A typical sealed speaker enclosure that holds a tweeter, a woofer and a midrange driver.

In a sealed speaker setup, the driver diaphragm compresses air in the enclosure when it moves in and rarefies air when it moves out. Copyright@2008 Sirnatec IT Centre

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2.16 Turn On & Off Computer 2.16.1) Identify PC Switches, Ports & Connectors

Power Onoff Switch Optical Drive Button

Power Cord Port PS2 Mouse Connector

PS2 Keyboard Connector

Parallel Port

VGA Connector USB Port Power Switch

Microphone Port

Network Port Speaker Port

Headphone Port

Reset Switch USB Port

Front Panel Front Panel Microphone Port Speaker Port

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2.16 Turn On & Off Computer 2.16.2) Plug in Cables on PC Connectors or Ports

Power Cord

VGA/Display Cable USB Cable Speaker Cable

Network Cable

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2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

Press Power Switch

Press here (Power Switch)

233

2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

POST screen on display on monitor

234

2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

Loading Window

235

2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

Window Welcome screen

236

2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

User Selection

237

2.16 Turn On & Off Computer 2.16.3) Turn On PC â&#x20AC;˘

Window Desktop screen

238

2.16 Turn On & Off Computer 2.16.4) Turn Off PC â&#x20AC;˘

Shut Down & Switch off PC

239