Radeons only : get radeonator and go into DX tweaks menu .
Turn W buffer off : this gives up to a 4% increase in performance
Turn signed volumetric textures off : gives a 4-5% increase , no image reduction
Turn Z buffer compression ON : up to a 10% increase with 3x zbuffer pression
Turn 8 bit stencil buffer ON : more performance for shadows .
Limit Z buffer to 24/16 bit : 8% performance increase
Turn alpha channel dithering off : for games with a big 2-d sky this speeds them up by at least 5%
ALL video cards :
Keep texture settings and resolution set at 16 bit , the image decrease is negligable compared to the FPS increase
Geforce : <insert here>
