White Laptop Screen - What causes a Laptop LCD Screen to turn Completely White? A white laptop LCD can be because of: (1) A defective LCD screen or motherboard (where the graphics are integrated), or (2) A loose connection between the video cable and the laptop screen.
Usually it's #2, which can be fixed by reconnecting the cable. If not, then you need to replace the laptop screen.
To troubleshoot quickly & effectively, get a functioning LCD screen from another laptop. Source Website http://LCDMonitorRepair.annics.com