Hello everyone, I have had my iBook G4 for about 3 1/2 years now. And I just got a message that says "Please restart your machine by holding down the power button for 50 seconds". I did that, let it stay off for about 5 minutes. Turned it back on and about 2 minutes later it says the same message again. I turned it off, and turned it back on. It seems to be error free for now. I have never dropped my computer! Please help! Thanks!