I tried running COD on a system with the following specs:
Core 2 @ 3.2GHz
4GB ram
9800 GT
With all settings set to low except model left at high the game was very playable only over water (35-50 fps). Once over land it turned into a slide show even with shadows turned off and settings at low.
Sorry for the late reply....it took some time to dig out the components from the archive