Artificial Benchmarks are .... artificial. Are you seeing lower than expected frame rates in games. Futuremark benchmarks are often.... errr.. optimized for Nvidia hardware
AFAIK, read into that what you will. Very latest drivers can help sometimes, although non-certified beta drivers can actually lower your score.
Also I would guess that 3dmark puts a greater weight on the CPU than you will see in real FPS in games
Anyway, I'm not really sure what reasonable scores are for that hardware, try looking on the website usually there are profiles to compare to.
I dont hold much faith in artificial benchmarks. You know what they say, the real question is...
Can it play Crysis?