My iMac was unplugged in windows sleep mode, and refused to start up. I panicked and tried various methods of plugging it in (w/o surge protector... etc.) Finally, as I got my dad to watch, I pressed the on button three times fairly quickly in desperation, and to my great surprise, it turned on. During my panic period, I began to imagine all the trouble of calling Apple, bringing it in, explaining the problem, then having to see if they'd swap it out. If so, my music was on the old one, as well as an OEM windows partition, games, and some of my better artwork. Whew... That scared me.