no the bsod doesn't affect the card - in fact it helps identify the problem. most cards have a 2d mode and an accellerated 3d mode (the 2d mode is only really ever used when installing the card for the first time or when you go to safe mode - also it does get used at other times but to a much lesser degree) so xp and modern os's use the 3d part to accelerate window drawing etc so when the 3d part goes down you get all kinda of weird effects - mostly consisting of lockups and bluescreens, however boot to safemode and they generally all go away (as its running in effect in 2d mode). anyway next step is to test the card in another machine just to be 100% sure then he can look at replacements.