I accidentally pressed the wrong key (not sure which) while typing and my laptop's screen went dim. I can't get it to go back to how it was. (I'm using Windows 7 64 bit.) What should I do?
2 Answers
The pressed key was F11 (without the Fn key pressed). The IdeaPad uses this key for "decrease brightness". F12 should do the opposite, but doesn't always work. To get it working, you need to edit the registry:
- Open/run
regedit
1 - Navigate to
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000
2 - Set the value of
"FeatureTestControl
to0000f048
(hexadecimal) - Reboot
- When Windows starts (or at any point while running), use the F11 and F12 keys to adjust the brightness of your screen.
- You might need to reinstall drivers for your graphics cards before this step.
- You might need to navigate to
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0001
instead ofHKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000
Source: IdeaPad P500 screen went dim
This worked for me on Windows 10
Open Device Manager (Search for it or right-click Start). Confirm the UAC prompt, if necessary.
Select Display Adapters and right-click on Intel HD Graphics 4000, then select Update Driver > Browse my computer for driver software > Let me pick from a list of device drivers on my computer. Choose "Display Adapters" as Device Type and select Microsoft Basic Display Adapter.