akm

I am using driver 13.12 at the moment. I have tried the latest drivers and a driver version older to 13.12 as well. If you happen to recall the driver version you are referring to, kindly let me know. By the way, Control Center (Hotkey) utility crashes every time I open it mainly due to the display brightness problem as it gives an error about brightness.dll. At least I would want to use the other functionalities of the Control Center. Do you have any suggestions to make the utility run? AMD Catalyst Control Center changes brightness and contrast at software level apparently. Even when I set the contrast to 0 in CCC, I can still feel the glare because the backlight is just too strong. Also, the image quality goes down.

Ok, thanks. I did try finding the registry tweaks and tried them too, none of them fixed the problem. The registry fix that was mentioned in most places is the below one: "Go to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000Next, go find:MD_EnableBrightnesslf2 KMD_EnableBrightnessInterface2 Set both to 0. Reboot." MD_EnableBrightnesslf2 key was not there by default, so I added it myself. It should actually be KMD instead of MD. I have tried both, by the way. I was quite hopeful that this would solve the problem, but unfortunately it didn't. If you have any suggestions, please let me know.

Hi Prema, I posted my notebook problem in notebookreview.com and got your reply to one of my posts. Since I haven’t seen you active in the P770ZM owners’ thread there for sometime, I am posting here: I have a P770ZM with AMD 8970M GPU. The display brightness controls are not working. Control Center crashes everytime I open it. Even the Windows brightness controls are not available. I should also mention that the notebook BIOS doesn't detect the AMD card. The system and the GPU work fine though, except for the display brightness issue. While trying to find a fix to the problem, I stumbled on this post. As you mentioned there that if the screen internal firmware can't interface with the EC then things like brightness control won’t work. I have an IPS panel (LP173WF4 SPD1) on my P770ZM. The current BIOS version of the system is 1.03.14 and EC version is 1.03.09 (latest). Even if I upgrade to the latest BIOS version 1.03.15, the EC version will remain unchanged and that won’t fix the problem. Do you have any suggestion? Could you please provide an EC version update which can fix the brightness problem? Alternatively, it would also be a great help if you could tell what registry tweak needs to be done.