I have a g4 tower 2004. It turns on. I get the apple on the screen. N then it shuts off. Or sometimes it will just say restart comp. Please help. I need to make my music.thanks
Most likely the PSU or motherboard is dead/dying. The motherboard could have some defective components due to age/heat/wear (i.e., capacitors) which WILL cause this symptom. Similar issues in the PSU results in the same symptoms.
You can try to take a look at the board/PSU yourself, but those G4's weren't the most friendly to service.