Samsung 535u3c (ATI 7500G) - cannot change brightness

[Konstantin]

Hello

Is there any way to change brightness on samsung 535u3c (ATI 7500G on board). It uses max brightness when it is connected to the external source and min brightness when uses its battery.

I tried Ubuntu 12.10, 12.04, OpenSuse 12.2, 12.3 - it does not change the brightness: Fn-Fx and software ways do not work. But in BIOS it works as expected.

All above for open drivers (the proprietary hang the system)

Thank you!