Coupling Win8 screen brightness can not adjust the small coup

Recently, the Lenovo Z500 notebook installed Win8 Professional Edition system, today using the Fn + F11 key combination to adjust the screen brightness, the screen suddenly becomes the darkest state, and can not adjust back. This made me anxious, and the screen was so dark. I tried various methods, and finally I finally solved it, and listened to me slowly.
First, by modifying the registry to solve the problem that Win8 screen brightness can not be adjusted.
The specific method is:
1, use the Win + R combination shortcut to open the run dialog, and then use the :regedit command to open the registry.



Open the Win8 registry method
2, open the registry editor, and then expand the location:
HKEY_LOCAL_MACHINE\\SYSTEM\\ControlSet001\\Control\\Class\\{4d36e968-e325-11ce-bfc1-08002be10318 }
Then change the value of KMD_EnableBrightnessInterface2 in 0000 and 0001 to 0.
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 netizens successfully solved the problem that Win8 screen brightness could not be adjusted through the above methods, but the author still did not solve the problem through the above methods.
Second, try to update the computer driver
After the author used the driver wizard, Lu master and other software to detect whether the computer has a driver problem, through the detection found that the CPU and motherboard driver available updates, but ultimately in accordance with the problem of upgrading and updating, still not solved.
Three, tried to update the Windows
into the Win8 Windows update, detected several updates, but after updating the driver, the problem remains.
4. Try to uninstall the discrete graphics driver
Because the brightness of the Win8 screen cannot be adjusted, it is usually related to the system settings or graphics card, so try to uninstall the driver of the discrete graphics card, because the notebook is i7 alone, in the graphics card The device can be found in the CPU with a graphics card and a discrete graphics card, so I first uninstalled the discrete graphics driver, and restarted the computer, and ultimately the screen brightness can not be adjusted.
At this point, the author has been a bit skeptical about whether there is a problem with the notebook screen, but in the end I still want to try again.

Re-send the notebook to the driver