Over the past few months I have noticed when I press the power button on my iMac (2007 aluminum version), i have to press it several times for it to do anything. And sometimes the fan turns on full power. meaning I have to remove the power cable from the back, put it back in again and turn it on But today, it wouldn't turn on at all for 10 minutes in several plug sockets, then it decided to power up. What is this problem? :L I'm backing up all my stuff now using Time Machine just incase.