Either the card's fan's is not working and it's overheating, or the card's video mem is bad. In either case, call them back and tell them of the problem, and see what they say about it.
Hi. I just recently got a new Geforce 6600 Gt OC (because my other one broke and I got it with the lifetime warenty) and I installed all the new drivers and everything. Now when I play Battlefield 2 or Call of Duty 2 I can play normally for about 2 minutes and then all of the sudden green and purple diamond/square shapes start to appear all over the screen and they keep multiplying. So any help is appreciated. (note that when BFG gave me my new card it was a bit different looking then my old one but was still called a BFG Geforce 6600GT overclocked, don't know if that matters anyway.)

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