15" MBP Screen Artifacts

So while I was playing Mount & Blade: Warband via Windows 7 bootcamp, I see these weird graphical artifacts after about an hour of heavy gameplay. It's kind of hard to tell from the image, but if you look at the text in the bottom left corner, the colors are distorted (it should be yellow text), and the artifacts are just to the right of the buildings.



I was thinking that this might have something to do with temperature as the artifacts started occurring much more quickly (20-25 minutes) once I restarted the game. My CPU (i7-3720qm got as hot as 100C, and my 650M was at about 80C).

I'm just past my factory warranty, so talking to Apple is kind of out of the question.

Is this a normal? Any way to fix this or should I quickly try to sell the computer before the problems get worse? I have the 15" cMBP mid-2012.

 

Bump!

Anyone?