I just installed the 64-Bit version of Ubuntu 12.04 on my newly bought Lenovo G580.
The brightness control was working properly using the Live CD and when I first started the installed version.
Then I updated Ubuntu and restarted my laptop, and suddenly now, I can't change the brightness.
I think its caused by some update. And then I went and checked my update settings, and saw that Unsupported Updates (precise-backports) were enabled by default. So now I need to fix this brightness issue somehow.
What should I do to locate the wrong update and remove it?
I don't even mind removing all the updates right now.
Thanks for the help. :)