According to an email I recieved from Sapphire today there's a new bios that fixes the issue - didn't have a chance to try it out though as we're really pushed for time testing the HD4870's (You'll see tommorrow, but they're pretty special).
Until they're avaliable it's only speculation, and certainly it all depends on what price they come in at, but I doubt your going to see a massive difference in most games.






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