okay...for those who complains about getting low framerates
here's a solution from a member in guru3d:
" I just figured out another tweak. This game isn't based on the Quake 3 engine anymore, but some of the tweaks still work. I tried out the hunkmegs tweak from Quake 3 on a hunch and what do ya know, it works
When you type in the console "/com_hunkmegs" you see how many megs of memory the game engine uses. By default it is only latched to 160 megs! You can set this value to anything up to 512 megs so that's what I did and my frames per second soared. Just type "/com_hunkmegs 512"
This won't take effect until the video is restarted so you can just type "/vid_restart" and it'll just reload the graphics settings with the hunkmegs latched to 512.
I can't believe this still works but it does. Try it out and youll see that in DX9 you'll be running smoother with the tweaks I just mentioned.
I hope this helps some of you."
according to many members over at guru3d...their framerates doubled by doing so