I have a Radeon HD 6310 in a Lenovo G575 with Window 10 64 bit. I am not able to change the brightness.Neither with the Fn-buttons nor in windows settings. A workaround is to change the brightness in the bios, but you won't believe: I don't want to restart everytime the sourrounding light changes
I tried different drivers: Catalyst-15.6-Beta, Catalyst-15.7.1, Catalyst-15.11.1Beta, Catalyst-Omega-14.12 (I think 15.7 and 15.11 had the same driver for this card)
Mainly I tried the suggestions of this thread: AMD Display Driver issues for Windows 10 with Radeon HD 6000.
Do you have other suggestions?