I did try another HDD temporarily and the computer still hung so I 
reconnected the original HDD.  There have been no error messages - the 
computer simply stops responding. 
I replaced the video card with an ATI 9600 (was an ASUS card originally) 
since that was about the only thing I hadn't tried. So I continued to 
try to get it to boot, finally got it to boot from an old Win 98 floppy. 
Then restarted and booted into the HP restore CD. Doesn't make sense to 
me, but then what do I know?  Got all the system restored, PCI cards 
installed, SP2 installed. It's running now and I'm running the 
BurninTest to see if it hangs in there. The most suspicious culprit is 
the wireless mouse (USB) but even that uses a driver from XP.
Ain't this fun?

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