Something is not right here...
All of my computers have P3 1.2GHz. One with 9800 Pro, one with 8500 128MB, both of which outclass the 9000, and the best I get with default graphics settings playing offline is about 30 fps in the tower/runway (previously about 24 fps, but the later betas did improve performance a bit).
Are you using default settings?
If I use max quality settings, I get 10-12 fps.
I am not especially happy with the way the ground objects look at default settings. As such, I have no intention of using higher performance settings than defaults.
I understand how someone with more CPU/memory bandwidth can smoke my framerates, but I don't understand how a 25% slower cpu and a 50% slower video card can get better performance.