3D Spotlight, a PC hardware resource WEB site, has introduced a fantastic OFP Tweak Guide, by Thomas McGuire. The guide will give you a detailed rundown on all of the regular and advanced settings available in the OFP preferences program and the OPTIONS settings, accessed from OFP's main menu. If you've always wanted to know what the GEOMETRY PERFORMANCE, AUTO DROP-DOWN and OBJECTS LOD settings were for, this is the place to go!
OFP player Mister Frag does, however, have quite a few notes about the tweak guide:
"The suggestion to run in 16-bit mode will cause more problems than it will solve; the explanation of how memory is allocated between OFP and Windows is wrong; moving the Geometry Performance slider position to the right will generally give you lower performance in the game; the explanation of Auto Drop-Down is backwards (i.e. suggesting that people with lower-end systems try lower settings); the information on the maximum number of lights is wrong; and the section on textures is a cut-and-paste job (compare the text for Cockpit textures and Special Effects textures).
I'm not saying that using 16-bit mode won't increase frame rates, but it will also reduce the Z-buffer depth and cause clipping errors and rendering artifacts. Whenever you hear stories about people being able to see through their character's helmet in third-person view, for example, that is the reason.
With some video cards you can work around this to some extent using a W-buffer, which OFP now supports. But W-buffer biasing may also require tuning using a program such as RivaTuner, available from Guru3D.
Overall, if the card is fast enough to handle 32-bit mode, 16-bit mode isn't worth the hassle.The W-buffer is a work-around for people who are forced to run 16-bit mode, because the latter doesn't have the precision for proper clipping in scenes with a lot of depth.
This is also why I said that the W-buffer requires tuning using a program such as RivaTuner. I don't think the Detonator drivers even expose the settings in the Control Panel, but they can be changed nevertheless.
You basically have to tell the driver how the bits in the W-buffer are allocated to increasing distances. If you want to avoid clipping problems with complex nearby objects such as other soldiers, you will probably wind up with roads or trees in the distance that appear and disappear. If you want to fix the latter problem, you'll wind up with being able to see through a soldier's head or helmet.
Again, the W-buffer is an attempt to fix a problem that is most easily avoided by using a 32-bit video mode."