Hi my 4870x2 failed a few months back and now after a long time i have been told because the 4870x2 has been discontinued and they are unable to get a replacement i will be getting a 6000 series card as a replacement i have asked which one in the series it will be but have not had a reply yet could someone please tell me if this is a fair replacement do any of the 6 series cards compare in performance to the 4870x2 any help would be greatly appreciated