Like on the previous response I will recommend to check with Lenovo to ensure that the Power Management is not creating any type of conflicts.
I will also recommend to see how the brightness is working when on the BIOS.
If possible please uninstall the Power Management and the Intel Graphic Driver
Then download and install the latest Graphic Driver from https://downloadcenter.intel.com/product/81499/Intel-HD-Graphics-4000-for-3rd-Generation-Intel-Core-Processors
Intel HD Graphics 4000 and Windows 10 & Windows 8.1 ( Brightness fix with latest driver)
Brightness Fix with Driver Date 8/17/2015 )
Brightness problem Solved
Intel HD Graphics 4000 with NVIDIA® GeForce® GT650M graphics.
Intel HD Graphics 4000 Driver, Driver Date: 8/17/2015
Driver Version: 10.18.10.4276
Make sure you backup your registry first before proceeding!!!!
open regedit in Run Command
Registry has wrong value:
Currently reads as :
"Edit DWORD 32 bit"= f000
Registry with New Value:
You needed to change the value in registry to: ( f008 )
"Edit DWORD 32 bit"= f008
Then Restart Computer
Brightness Fixed with Latest driver.
Let me know if this was helpful to you
Thank you for the information you kindly provided.
np was your issue resolved ?
If not, try updating Windows and also update your graphics driver to the latest version, you can download it here:
Note: The driver is generic versions and can be used for general purposes. However, computer original equipment manufacturers (OEMs) may have altered the features, incorporated customizations, or made other changes to the software or software packaging they provide. To avoid any potential installation incompatibilities on your OEM system, Intel recommends that you check with your OEM and use the drivers provided by your system manufacturer. Intel and the computer original equipment manufacturer (OEM) may not provide technical support for some or all issues that could arise from the usage of this generic version of software drivers.
I have a Samsung ATIV Book 8 touchscreen 64-bit windows 10 laptop and I am having the same problem that np had. I already had the Intel HD Graphics 4000 driver version 10.18.10.4276 installed so I uninstalled it and then installed it again. I then looked up the registry value and it read f908, not the f000 value that is expected in the solution. Anyhow I changed the registry value to f008 and then restarted but the brightness control issue still persists. Is there another registry value that I should be entering since I have a different machine than np? Or is there anything else that I can try to resolve this issue?
Thank for your time and assistance.
OMG that worked!! You're amazing hoohah! I don't even know how many hours I've spent trying to figure this out.
Summary of my fix: I followed the same steps as JohnRoss2113 suggested, except the path to the registry value that I needed to change was slightly different. This registry value original read f000 and then I changed it to f008, like in JohnRosss2113's solution. Also, I already had the latest version of the driver installed and I did not uninstall the driver and then reinstall it this time. The path to the registry value that I changed is below with the differences from JohnRoss2113's suggested path in bold:
Thank you so much for your help guys.