I finally got this to work. It turns out my problem had to do with Nvidia's TwinView. I added some single screen metamodes to my xorg.conf and now it runs properly. However, I get a lot of choppyness in the display. I have OpenGL vsync set using the nvidia-settings utility as well as in my .bashrc environment variables. When I run the demo I get the same results with sync to vblank on and off. How are you guys seeing it? Is it silky smooth or are you getting choppyness too?