Unplugging the AC power makes the screen brighter plugging in the AC power makes the screen less bright Should be the other way (less brightness is less energy consumed). Dell 620 Version-Release number of selected component (if applicable): gnome-power-manager-2.17.91-1.fc7 How reproducible: 100%
What's the brightness settings in gnome-power-preferences?
I don't see any. gnome-power-manager-2.18.1-2.fc7 Attaching screenshots
Created attachment 152316 [details] Screenshot-Power Management Preferences.png
Created attachment 152317 [details] Screenshot-Power Management Preferences-1.png
what does "lshal | backlight" print?
Created attachment 152466 [details] lshal -l output # lshal | backlight -bash: backlight: command not found [root@localhost ~]# lshal | grep light [root@localhost ~]#
Looks like it's your BIOS setting the brightness (I too have a Dell that can do this) -> not a g-p-m bug