We have found display issues on Delta Force: Xtreme and Joint Operations related to the Nvidia ForceWare Version 81.85 drivers. Currently only some of the AGP and PCI Express models of Nvidia 6800 chipset are affected. If you are experiencing issues on this version of Nvidia ForceWare please download a one of the previous versions of the Nvidia ForceWare drivers.
For Windows 2000 / XP visit http://www.nvidia.com/object/winxp-2k_archive.html
For Windows 95 / 98 / ME visit http://www.nvidia.com/object/win9x_archive.html
We're currently in contact with the developers at Nvidia and are attempting to promptly resolve this issue with future driver releases