weird graphic problem

I have got a real weird graphic probolem: In every game i play, one or more players will start to loose control of their bodies. no joke. It looks funny at first. their upper body starts rotating, their legs point to the sky.... the point is: you can still play. you can pass to the guy and he catches the ball but: it looks really mest up. you can shoot, but the ball isn't exactly in his hand...you can block shots, but he is not making the right movement, it looks like he doesn't even touch the ball...

I have no clue!!!

game reinstalled....graphic driver new....eapatch installed....

Graphic board damaged???

its a nvida fx5900....

first time i heard of this problem...got any screenshots?