Ok on my notebook I noticed that when I plug in for ac power the screen dims, but when I unplug the screen brightens. I remember it working the other way around and I am sure it's doing it backwards. What can I do to fix it?
Maybe the setting are switched around? Have you looked at how your power is set up. I believe there should be (possibly hidden) an icon in the bottom right corner, in the tray, that allows you to adjust it to desktop use and portable, etc.