[->Zeke]

Have you tried just the processor, no RAM, vid etc...? It should at least beep at you then

Yeah, tried it, no beeps. (Speaker is connected properly.)

Do you have an old MOBO you can put your processor & RAM into to check those (sounds like you don't)?

Nah, the only other motherboard I have is an Abit KT-7 which won't support the newer Athlon's. (Got a Duron 800 in it now.)

Is there perhaps a loose case screw sitting where it shouldn't (give it the shake test)?

Nah, I transplanted everything to a new case and same results.

Does the mobo/proc/RAM operate with the case mounting screws removed (perhaps a cold solder joing that flexed open)?

Didn't try that, but I will add it to my list of things I'll try before I send 'er back.

It posted once for him, so I assume that's not the problem?

It posted about a dozen times, actually.

[->Rob]

Make sure the jumper for CMOS clear is set on "normal" (not clear).

First or second thing I checked. I did try clear the CMOS just to see if it was the issue, but the jumper is back where it's supposed to be.

Then I would check that I didn't crack the Athlon's die when applying the heatsink.

Yeah, that's next, though I've been reluctant to pull the heatsink off because I'll have to reapply my thermal paste (and remove the old paste) to do so. I have never had problems with this though, and the CPU/Mobo *did* work for the first half hour of my journey. I doubt a CPU with a cracked die would operate for that long.

Another possibility is that the memory is ECC. Most "consumer" chipsets coming out now are not supporting such memory.

This is brand new Kingston PC2700 DDR. One thing I thought about was putting it into my "old" system (KT7-RAID.) Are newer PC2700 memories backwards-compatible to a system that normally runs on PC100 or PC133 RAM?

Sigh. I'm going to keep trying things here, I guess the next step is popping the CPU out and taking a look at it. I'm thinking it's the mobo, but I figured if I did something screwy to it, it'd at least beep at me or not power up at all...