I guess I'm not familiar with this product.
If it's the first series of GeForce, you might try dropping back to the 6.67 or 6.47 versions of the drivers. The streaking behavior you describe is usually only seen on low-end ATI cards.
Switching drivers (the ones at
www.nvidia.com are rarely the best) and then reinstalling DirectX 8.0a on top usually clears up issues such as these. Please let us know if you need any more help. Drivers may be found at
www.gamers-ammo.com