Lenovo IdeaPad U450 User Manual
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Chapter 5. Troubleshooting
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 touchpad.
- Press any key on the keyboard.
- Press the power button.
- Press Fn+F2 to confirm whether the LCD screen
has been turned off.
Problems on Graphics card switch
Before switch.
•
Ensure:
- Only use the Switchable Graphics in Windows 7
and the “Graphics Device” option in the “BIOS
Setup Menu” is enabled.
Can not be switched.
•
The following conditions prevent the graphics card
from being switched:
- An exclusive mode D3D application is running.
- An OpenGL application is running.
- An external display device is active.
Problems that might occur.
•
Most existing D3D applications running in
windowed mode do not prevent graphics card
switches, but some D3D applications will not
recognize the graphics card switch and will abort
resulting in a black display window.
•
Some existing player applications will not properly
respond to graphics card switches.
Note:
Either case, needs a restart of the computer.