Re: low benchmark scores?
No. Don't risk destroying your new card for negligible performance gains. Your computer is performing very well as it is. My system scores like 10900 in 3DMark03 with everything at stock, and about 12500 with just the video card overclocked. I promptly stopped using Futuremark benchmarks since I've come to realize how completely useless they are at gauging your system's performance.
I destroyed my old processor (Pentium 4) in the pursuit of better performance, and while this Athlon 64 is a lot faster, it was very expensive to replace - the same goes for your video card! Be happy with what you have! Your system is extraordinary compared to the average PC gamer's system out there!
__________________Core i7 920 @ 3.2 | ASUS P6T Deluxe V2
6GB Mushkin DDR3-1600 RAM
eVGA GTX 570 SC | Auzen X-Fi Prelude 7.1