Radeon 8950M brightness issue

Hello everyone, I have searched the forum and did not find any clue to the given problem, so there it is:

After upgrading from GTX 240M to Radeon HD 8950 in my M15x I have encountered a weird issue - I can no longer adjust brightness, it is constantly stuck at full glow, the slider can go to hell and back and the backlight won't budge. Any suggestions? Could it be a driver issue (i've got the newest)? Or just some sort of a registry error? I have found a few tutorials for resolving that, but none of them worked, I've tried using Adrenaline to do something but no luck, I've found a registry editing manual, but the reg key given in it was non-existent in my case. Has anyone encountered the same issue?

 

Which driver did you use?

 

aticfx64.dll, model WDDM2.6, version 26.20.12001.11014

 

Have you tried the Radeon Pro/enterprise driver?

 

Attempting it right now

After installing the Radeon Enterprise all it did was recognizing my Radeon HD 8950 as AMD Firepro 6100M and that's it. I'm currently updating the drivers via Driver Booster to see what results that will give me (unless it reverts it back to recognition of HD 8950...)

After the Driver Booster update there is still no change. Any further ideas?

 

Any driver newer than 17.3.3 breaks brightness/acpi methods when using Radeon cards in old Alienware

 

^Yup my 7970M had same issue in M15x.

Need to use a older driver if you want brightness control.

 

Ok, I see. Are there any downsides when using older driver? Performance drops, anything?

 

Not really, these old GCN cards really do not benefit from new drivers, the architecture is too old. Only thing is if some games have bugs with old drivers, you may need to update.


Ghetto fix method: you can return brightness control on a single card when using new drivers by disconnecting the AC adapter, the plugging it back in. This should allow proper brightness control