Looks like your graphics card is overheating to me, but I also think that if that were the case it would look a lot worse than that. I've seen similar problems in Mass Effect 2, where the faces and armor never loaded properly due to graphics card restrictions, and instead they just had black stripes all over them. So I would expect more scattered graphics issues if that were the case.
Does this happen all the time, or is there some pattern? 10-15 mins in? Only when hosting mp?