Hi everyone, should I be worried. My Intel iMac (20" 2.0 ghz) started making a humming sound about a week or so back. I bought the computer when they first came out (February?) and it had been perfect up until now, at first I thought it was the fan kicking in cuz it has been hot and the computer is not in an air conditioned room but it sounds like a psu humming sound to me. Is there a track record with the psu, I know there were issues with the G5 Imac's, should I call apple?