Ok here are my specs on my 9400.
Duo Core 1.83ghz
2GB RAM @ 667mhz
7900GS
100GB HDD @ 5200rpm
I ran Crysis fairly smoothly (not amazing, but certainly playable) at 1280x1024 i think it was. Textures were turned to high, Postprocessing and Shadows were set to low, and everything else was medium and it looked very good. I ran fraps benchmark from the plane jump to the end of the demo.
2007-10-27 17:50:33 - Crysis
Frames: 67091 - Time: 2774682ms - Avg: 24.179 - Min: 0 - Max: 70
No idea why min frames says zero, I must have started the test before it finished loading is my guess, but it never went below 13 according to my previous run throughs. Not bad, I'm guessing with new drivers and a few tweaks I might be able to get it running better, let's hope. But from the performance I had on the demo, I'm going to buy for sure, the suit provides for some awesome combat sequences and the game is just gorgeous.