Hello all, just a little note that may help someone out there. I have a Powerbook G4, 4yrs hold. Recently it would simply not turn on: no fan, no noise whatsoever. Battery charging, regular lights on the power chord but still no joy (the battery was anyway misfunctional beforehand and the computer would not stay on at all if unplugged, even if the battery showed 100%). I thought of dead motherboard, so I opened it up just for the fun of it thinking: "Hey, maybe there is a big red glowing X where the problem is!" Not so obvious. However: the power button on the chassis that holds the keyboard is connected to the mo-board through the same flat cable as the keyboard. For whatever reason the connector had come just imperceptibly loose (not visibly). (Note: the computer had fallen about two months ago, but was working after the fall). So, I pushed it down firmly but genty and -voila'- the computer turns on again! (Well, the battery (or the DC board) is still shot though....) So I have the kitchen computer back online!!! Well, I just thought that since it happened to me, it may happen to someone else and this note may be of help. Cheers.