Well, some people have put up a so called "remedy" for the afflicted cards. It involves removing your card, putting it into an oven propped on aluminium foil and baking it. I can't remember the details, I'll look it up in a bit. Apparently the problems were all caused by faulty soldering, which cracks up when heated and cooled rapidly within the laptop. This resolders the parts, allowing it to work again. At least until the next time it cracks.