screen suddenly gone darker

[Duncan Lithgow]

My screen has just gone suddenly darker - again. It did this a while ago 
in windows and now it's done it under fc3. I'm guessing that it's a 
hardware issue because it's the same when i goot to windows _and_ it 
effects the grub boot dialogue too! That means whatever's happening it's 
early in the bootup process. That's if software even plays a role at all...

I'd love some suggestions for what to do about this - how to pin down a 
cause. I've got brightness and contrast turned up to max - if it happens 
yet again, then things will be annoyingly dark.

Duncan