I'm hoping someone here can help. I've been having issues with my Mac Pro for two days. It started yesterday with my computer suddenly shutting off out of nowhere. This has never happened before, and I have a battery back up, so it shouldn't happen. We did not lose power and everything else plugged into the UPS remained with power. Later that day my computer just froze. The computer remained on but everything was frozen. Had to do a hard restart. Today it froze again out of nowhere. I tried a hard restart. The computer restarted and then immediately shut itself down again. I restarted it again, it went through the start-up process then it shut down and restarted again by itself. It then once again froze. I just restarted it again and I'm hoping it stays this way, but I have nothing else running besides Firefox. I'm on 10.5.8 Any ideas? Thanks.