My friend left his MDD g4 on for two days, and then when he tried to take off the screensaver, it froze. Now when he tries to start it up, it won't power on, and the button flashes quickly, then slowly, then quickly. He tried unplugging the tower, and then plugging it back in to no avail. No signal to the monitor (VGA), but the fans seem to turn on. I recently installed a PCi card on his computer (digi 001), but the computer was running fine for about a week before this happened, so I assume it wasn't that. My friend pointed out that when he first bought the computer in January, it made a strange beeping sound, which I don't know if this is related or not. Thanks a lot, all.