Win8.1 screen brightness can not be adjusted how to do?

win8.1 screen brightness can not be adjusted how to do? Will explain win8.1 brightness can not adjust the solution, many users said that the process of using win8.1 too, want to adjust the brightness but no response, how is this going? Please Look at the following.
Method 1,
1, use the Win + R combination shortcut to open the run dialog, and then use the :regedit command to open the registry.

2, after opening the registry editor, expand the location:
HKEY_LOCAL_MACHINESYSTEMControlSet001ControlClass{4d36e968-e325-11ce-bfc1-08002be10318}
Then change the value of KMD_EnableBrightnessInterface2 in 0000 and 0001 to 0 Just fine.
3. After the completion, restart the computer.
Note: If there is no 0001, only change 0000, and if you can't find the KMD_EnableBrightnessInterface2 registry key in these two items, you can create a new one, and the new type is REG_DWORD.
Some users have successfully solved the problem that the brightness of Win8.1 screen cannot be adjusted through the above methods. If you use invalid, please continue to look down.
Method 2,
Because the brightness of Win8.1 screen can not be adjusted is usually related to system settings or graphics cards, so try to uninstall the driver of the discrete graphics card, because the notebook is i7 alone, in the graphics device It can be found that the CPU comes with a graphics card and a discrete graphics card, so we need to uninstall the discrete graphics driver and restart the computer, and the screen brightness is still not adjustable.
The next operation is to use the driver wizard to install the discrete graphics driver again, and then this time I uninstalled the HD4000 core graphics card that comes with the Core i7 processor. Surprise is that when the HD4000 core graphics card is uninstalled, The screen of the notebook turned out to be magically bright, and the screen brightness can be adjusted normally.



Using Master Lu’s driver butler again, I installed the HD4000 core graphics driver installed on the i7 processor again, and there was no problem. The screen brightness was still adjusted normally.

The above two win8.1 screen brightness can not be adjusted solution, let's try it~