Glitching graphics

First up, my specs:

Sempron 2800+ (Skt 754)
ECS KM8M800-M2 mobo
512mb Ram
Palit GeForce 6600 AGP 256mb
AC 97 audio.

Now, the problem:

I have recently installed a new mobo in my pc after the last one shorted. Everything else is running ok, except GW.

When the game launches, I keep getting what I would describe as tearing of the graphics (distoted or textureless polys). As a precaution I tested a few more games (OutRun 2006, F.E.A.R., Dawn of Magic), which all ran glitch free.

I also stress tested the GPU with 3D Mark 06, which also displayed no graphics glitches or errors. I am running the latest Forceware drivers, and the most up to date mobo drivers.

Any suggestions?

You got a good one.
What fried the last mobo? Power Spike?

No (I'm surge protected).

When I took the mobo out there was nothing obvious. I just tried to boot up, heard a small noise, and the boot failed. I tried again a few times, no life. I even left it over the weekend....no change, so I swapped the mobo, and it booted.

Looks like I have a real strange one don't it.