Computer is an AMD Athlon 850mhz and has one fan on top. Not sure what could cause the hang ups. Freezes during installation of windows xp, have formated HDD 5 times and replaced video and audio cards. Still freezes, random times, but never in safe mode. I can use safe mode with networking and all is well, but no sound and video isn't full rez. Anyone? No viruses or files installed and freezes, usually hangs late in windows installation. But like I say never hangs in safe mode. Could it be overheating? How do I check?