I have a 2005 Power Mac G5 with Dual CPU's (think it's the 1.8 GHz version). Sometimes it doesn't boot; when I press the start button, no boot chime, and if I leave it on for awhile, the fans fires up at 100%. If I do a force shutdown, and start it a few times, the boot chime comes up, and it boots correctly to the desktop. Here, I would think that it could be a PSU issue, but wouldn't it be totally dead if it was the PSU? Because I can get to the desktop on 7/10 tries. But it also sometimes freezes while using it. It just freeze the current picture, and I cannot do anything. If I leave it on, the fans fires up again. So I'm more thinking about if it's a RAM issue? What do you think? And have anyone else have had issues like these? Thanks!