If the driver stops responding it's likely faulty hardware. My faulty 4850 did that. RMA your card.
If at first you don't succeed, rage at the drivers.
I have owned BOTH Nvidia and AMD cards, each have their own share of problems. Driver or hardware, both have problems.
People need to stop being fanboys and posting worthless garbage, and focus on solving their individual problem, and not boycotting an entire brand over one issue.
RMA your card, it's the best course of action.
Instead of people offering to help solve the OP's problem it turns into a huge turd-sling fest about which side is "better" than the other. You know about arguing on the internet; even if you win...