Google "Video Card Overclock" or something along those lines. Or goto the Overclock section of these forums and check out the nice guide there.
I'm running a 6600gt with no overclocks at all and only 512 mb of ram. I got a 2200 on 3dmark03 at first and was very disappointed. I messed with the forceware settings a little (did not overclock) and got a 7746 the next time. But even before i messed with the settings the thing ran all my games (Battlefield Vietnam, City of Heroes, Warcraft, HL2, Counterstrike) at high with almost no hitches.
As long as your pleased with your gaming performance then dont worry about some lousy score.
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