These are the scores I got with my 6600GT...drivers are shown, CPU was a 35w 2400+ XP-Mobile , 1gb of RAM:
Stock @ DDR400 - 7530 - 3dmark03
Stock @ DDR470 - 7555 - 3dmark03
555/999 @ DDR470 - 8247 - 3dmark03
550/1003 @ DDR400 - 8192 - 3dmark03
Stock @ DDR400 @ 2.5GHz - 71.81 Drivers- 7025!?! - 3dmark03
Stock @ DDR400 @ 2.5GHz - 66.93 Drivers- 7582 - 3dmark03
Stock @ DDR400 @ 2.6GHz - 66.93 Drivers- 7627 - 3dmark03
Stock @ DDR400 @ 2.6GHz - 66.93 Drivers- 7627 - 3dmark03
564/967 @ DDR400 @ 2.6GHz - 66.93 Drivers- 8252 - 3dmark03
564/1003 @ DDR400 @ 2.6GHz - 66.93 Drivers- 8347 - 3dmark03
564/1011 @ DDR400 @ 2.6GHz - 66.93 Drivers- 8388 - 3dmark03
564/1046 @ DDR400 @ 2.6GHz - 66.93 Drivers- 8476 - 3dmark03
564/1046 @ DDR400 @ 2.6GHz - 66.93 Drivers- 8481 - 3dmark03(Build 360)
564/1109 @ DDR400 @ 2.5GHz - 66.93 Drivers- 8574 - 3dmark03(Build 360)
Stock @ DDR400 @ 2.5GHz - 71.84 Drivers- 7663 - 3dmark03(Build 360)
566/1101 @ DDR400 @ 2.5GHz - 71.84 Drivers- 8134 - 3dmark03(Build 360)
564/1101 @ DDR400 @ 2.5GHz - 71.84 Drivers- 8615 - 3dmark03(Build 360)
Stock @ DDR460 @ 2.53GHz - 71.84 Drivers- 7742 - 3dmark03(Build 360)
520/1101 @ DDR472 @ 2.479GHz - 71.84 Drivers- 8300 - 3dmark03(Build 360)
570/1121 @ DDR472 @ 2.479GHz - 71.84 Drivers- 8747 - 3dmark03(Build 360)
looks like your stock was a bit lower than mine, however I believe my CPU was at 2.5GHz at mostly, all times