External monitor has wrong resolution

I have a 23' external monitor (through VGA) which always worked at 1440x900 and looked amazing. Today after I unplugged it, it still says it's working at 1440x900 but it's actual resolution is bigger.

I've tried unplugging, rebooting, Detect Displays, change res. and change back but no dice. Any clues on what might be happening?

Thanks!


Solution 1:

Try resetting the PRAM and see what happens.