need some help :/

So, I recently made a new computer (I'll list the parts at the end of this post), and it was working great for a few weeks, but more recently it's started crashing on me. At first it was rare, but today it started doing it almost constantly. Things will be fine, and then the image will freak out, and I'll have to restart it. I suppose the best way to describe the distortion would be that it's similar to the kind of glitchiness you'd get from the missingno. glitch in pokemon.

I'm thinking it's the video card, but I'm not really sure. I ran memtest last night and it didn't show any errors, so I'm sure it's not the RAM, at least.

My setup:

Motherboard: Intel DX38BT

CPU: Intel Q6600 quad @ 2.4 GHz

RAM: 2GB Patriot DDR3. It's supposed to be 1333, but it's set at 1066 due to my FSB, and I don't really care enough to raise my FSB and change that.

GPU: EVGA 9600GT Superclocked Edition with 512MB GDDR4 (I think)

HDD: Seagate 500GB SATA drive with 16MB cache and a 3.0 GB/s rate of transfer, or something

PSU: Corsair 650W

Anything else you guys wanna know?

yes