This is driving me nuts. Bought a used Powermac G4. Great buy...I think its the 500Mhz model. Anyways, the stupid thing...when you turn it off, then restart it, nothing happens. The Fan Runs The lights inside come on. The CD light flashes Thats it. I turn it off, then turn it on, same thing. Unplug hard drive data cable, everything works fine (of course it wont boot) So I plug everything in, let it sit over night, bammo, it starts up. Also, it seems that in order to do this, you HAVE to press the keyboard start key, not the power button. What on EARTH is this about?