There is a known issue for players with any ATI video card with ATI Catalyst Control Center installed. If you have Anti-Aliasing activated through the Catalyst Control Center, you will experience graphical bugs. To fix this, you can go to the Catalyst Control Center and turn off the Anti-Aliasing feature or you can go to the AMD site and download and install a CAP file. The CAP file will tell the card not to use the AA feature on Duke Nukem Forever so you will not have to manually turn on and off the AA feature.
Duke Nukem Forever offers in-game Anti-Aliasing support for ATI cards. Anti-Aliasing can be turned on in the Options menu.
To get the CAP file, please go to the AMD site: http://sites.amd.com/us/game/downloads/Pages/radeon_win7-64.aspx