What happens when you run the faulty card? Does it also crash continuously? If it's faulty, and it sure sounds like it is, you should be able to RMA the card.
when i run the faulty card.. it doesnt have any problem when loading windows..but when i start to play any games(PES, Metro 2033, RE5, Batman AA), it start to hang and crash...
For this kind of problem i can use the warranty right?