Lenovo IDEAPAD U330 User Manual page 62

Chapter 4. Troubleshooting
If these items are properly set, and the screen remains blank, have the
computer serviced.
When I turn on the computer, only a white cursor appears on a blank
screen.
Restore backed-up files to your Windows environment or the entire
contents of your hard disk to the original factory contents using OneKey
Recovery. If you still see only the cursor on the screen, have the computer
serviced.
My screen goes blank while the computer is on.
Your screen saver or power management may be enabled. Do one of the
following to exit from the screen saver or to resume from sleep or
hibernation mode:
Touch the touch pad.
Press any key.
Press the power button.
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