That really sucks
Sorry to hear that man.
This page may help you identify what's gone wrong according to which artefact you have
http://www.playtool.com/pages/artifacts/artifacts.html
Hope whichever company you got it from has a speedy RMA service.
Why not look at the gtx570 if you can get one for a similar price? It would be much better. But I understand if you prefer AMD.