3dmark03 tests purely your gpu power
its not a good test of overall system performance (ie cpu, ram, etc)
aquamark is a better benchmark because it is based off a real game engine, but even then the bulk of the score is still gpu dependant
i'd recomend getting a program called "benchemall" google it and download it, its free... and it allows you to standardize benching the latest games like farcry, ut2004k... and since these are real games, it is a better test of your overall system performance in real game tests