janith wrote: > from fn key it work fine from 3.2.* kernels. i installed latest > kernels. but from them its not working. also i updated xserver-xorg. > > this are from lspci Intel Corporation 3rd Gen Core processor > Graphics Controller VGA compatible controller: Advanced Micro > Devices, Inc. [AMD/ATI] Thames [Radeon HD 7500M/7600M Series]
You could try the suggestions here: https://wiki.ubuntu.com/Kernel/Debugging/Backlight Andrew.
