I did OC my CPU from 2.2 to 2.4GHz. My RAM is in dual channel and my hard drive is only 80GB and defragged when the test was done. That's about the only difference I see from what you have. My RAM might be better, I don't know. I changed the timing for RAM just slightly in BIOS. I doubt sound cards have anything to do with it.
If you look at my stock settings for the video card, they are quite high already @ 480/1.12. I can just imagine if I were to turn it up a notch. I'll probably be running in the 8000 range.