I thought about trying a memory tester, but I suspect it will simply
blue screen on me during the test (it's consistent about blue screening
as soon as it has warmed up). Good tips about the PS rails. I'll try
reseating everything when I start to remove hardware.

The computer has been overclocked in the past (video, cpu and bus), but
at the moment it is running at stock speeds and the memory (and the
video card) are actually running a bit underclocked. (Card came that
way from the manufacturer that way and as for the memory, I purchased
DIMM's to use on a Athlon 3200 but ended up building it with a 2500.
(With the intention of overclocking to 3200 speed, but it was never
entirely stable at that speed, it would blue screen on me at bad
times...like when I was winning during a game! A rarity for this old
man. :-) ) Besides, it had been running rock stable until just
recently. The problems happened suddenly, as though someone had
"thrown a switch" and turned on the blue screens. This is why I'm sure
it is a hardware failure of some sort.

Craig