I'm not sure what features are cut down to make the "Go" version of the FX6800, but I'd expect the current driver software for any recent nVidia card to offer OpenGL 2.0, rather than the 1.5.2 yours offers (I have a positively ancient FX5200 and the drivers have updated it to OpenGL 2). Go to www.nvidia.com, go to Download in the top bar of the page, click Download drivers in the menu that pops up, then in the boxes that appear in the middle of the screen click "Graphics driver", then "GeForce and TNT2", and then your Windows version (XP/2000 by the look of it), and click the Go button under the boxes. That will take you to the page for downloading the installer for the latest driver. I don't know if that will fix your problems, but it should at least reduce them.