Well, I have progress to report... Tried the "easy" tests (hold down insert, mobo outside case, etc) with no joy. Swapped in the Duron 800 from my other box and it POSTed, I had display, a single beep, etc. So it would appear my Athlon XP 1700 is dead. Which I don't get, because CPU temps never went high, I never changed the voltage, etc. No cracked die or sign of any "damage" to the CPU... But given the fact that the mobo/RAM are okay for at least POSTing, the CPU would seem to be the culprit. Which really bites.

So I guess I've got to send it back to NewEgg, and pay their damn 15% restocking fee, not to mention they subtract for "current market value" of the CPU. I'm now debating whether to return it to them for a replacement or just return it for a refund and look elsewhere for another Athlon CPU.

I just wish I had some idea of what went wrong with this thing. When I looked in the "health monitor" the CPU temperature never went over 52 or 53 degrees. Don't they do burn-in tests of these things before they ship?

Oh well. Time to put everything back together and pack up the frickin' CPU. Thanks for all the tips, guys. Glad I didn't send my motherboard back!