If you still suspect heat as a possible cause, then open the case and place a floor fan and blow air on it and see if it still hangs.
Sadly, no search here, wish there was one.
From your thread it looks as if you have eliminated the P/S. Here I assume you went larger, not just the same in case it is an underpower situation.
Remove / unplug everything you don't need (sound cards, other IDE devices (CDROM, FLOPPY) and USB,Parallel and serial devices and see if it still hangs? If not add them back in one at a time and see when it starts to hang. Try to eliminate possibilities.
What PCI devices do you have and consider moving to different PCI slots.
If after all this you have the same problem look to CPU, motherboard or hard drive.
Here is my problem.... thought I would try for help someplace else (here).
http://forum.pcmech.com/showthread.php?s=&threadid=92669
BTW, Im a noob here, where is the search button?
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