[Rowddy]

maybe this helps a bit i have a 7800 GS and i play at the higest settings atm and it plays very good . screenresolution is 1280 x 1024. the card settings are
colorquality: highest 32 bits
system performance: quality
Anisotrop: auto

The game settings are in Stab..
hardware shaders: on
effects lightning: enhanced
tree rendering: 3
water rendering mode: 4
cloud rendering style: new style clouds
enable 3-d models of human gunners: on

Hope this help to give you an idea