GPU gems 2 demo

[MrIdiot]

i am trying to run the demo of the atmospheric scattering program from chapter 16 of GPU gems 2. when i run the exe file i just get a black screen. can anyone tell me whats wrong and what i need to do to run the demo? thanks

[bladder]

What handrware do you have?

[MrIdiot]

i have an nVidia 6600. i have run a few other Cg programs ok.