What is your 3DMark score?
Mine:

You can overclock if you want and setting your graphics quality to low settigs or performance will give you a better score for the most part.
pc specs:
OS: Windows Vista Ultimate
CPU: AMD Athlon 64 X2 5200+ @ 2.6Ghz
Ram: 1.5Gigs @ 667Mhz
Graphics: NVIDIA GeForce 7600 GS @ 478Mhz with 512mb Gddr2