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).
Version-Release number of selected component (if applicable):
What's the brightness settings in gnome-power-preferences?
I don't see any. gnome-power-manager-2.18.1-2.fc7
Created attachment 152316 [details]
Screenshot-Power Management Preferences.png
Created attachment 152317 [details]
Screenshot-Power Management Preferences-1.png
what does "lshal | backlight" print?
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lshal -l output
# lshal | backlight
-bash: backlight: command not found
[root@localhost ~]# lshal | grep light
Looks like it's your BIOS setting the brightness (I too have a Dell that can do
this) -> not a g-p-m bug