Apart from any clock differences, stock fans... Not much a difference. Same GPU. You can get an 8800gts 512mb for significantly less, which is the same GPU as the 9800gtx except with slightly lower clocks and "Inferior" HD video acceleration. Which is to say, they perform pretty much exactly the same.
Yeah, core clock should contribute more to performance than the memory clock. Not by much but whatever, Sexy OC'd silicon goodness ftw!![]()