I purchased a GTX580 from EVGA and it was factory overclocked (797 core 2025 memory). Anyway, I ran the extreme preset on Kombuster and scored a 530 with 14fps. I'm looking at other scores online and at stock speeds people are getting in the thousands easily. Is something wrong with my card?
nothing is wrong with your card.
nvidia gtx580 and gtx570 have a piece of hardware that when enabled with the drivers, detects extreme demanding applications like furmark (and furmark based apps like msi combustor), and throttles the card down internally.
this is done because these apps put a load that is unnatural. by this i mean that the amount of load they put is a lot more than what kind of load any game will put.
when nvidia design the card, they design the power circuits with a certain practical and real world load in mind. these apps always put a load higher than that. this always causes increased power consumption, something the card is not designed for, potentially harming the $500 investment.
so these cards throttle down the card. but dont worry, you will never get the card to throttle down in any game you play. think metro 2033 @ ultra 2560x1600 at ultra and 16xAA. so dont worry about that.
i would advice against using these application to submit the scores. they can cause harm.