I've got a PowerMac G4 MDD (1.25GHz) (2003), which has been running 10.5.8. I shut it down recently (I rarely do this) and it wouldn't power on again. No power light. Nothing at all. I unplugged the power cord for a few minutes and then re-connected. After that it powered up again fine. Shut it down again a day later to see if the issue had been resolved and again, I had to unplug power, wait and replug to get it to start up. This time clock was reset. Alas I don't know much about computers... What needs to be replaced? or is it finally on it's last leg? Any help? Thanks in advance.