I have a late 2010 3.2ghz i3 iMac.

For six months, the screen has been nice and bright.

Now, it is very dim...like it looks before the screen goes to sleep.

I have done all of the usual steps:

Zapped the PRAM, left it unplugged for a night, booted into root user to check if it was a software issue, checked the profiles, ran f-disk, started it up with CD...all without any luck.

Of course, I also checked the display preferences.

Is there anything thing else I have overlooked?