[Wylug-help] OT: Dim screen on laptop

[Anne Wilson]

From time to time I have problems with the screen dimming on my Acer laptop.  
It's as though it's on the battery mode, even though it's plugged in, and 
it's giving me headaches.  On one occasion, booting into windows then back 
into linux did get the brightness back.  On another occasion, removing power, 
forcing it onto battery, then restoring power brought it back.  Sometimes, 
though, I just can't get it back, no matter what I do.

Has anyone met this problem?  Is it hardware or OS?

Anne