- Pixel Shader 3.0
- Vertex Shader 3.0
- Geometry Instancing
- PureVideo
- SLI
The main features of the XFX 6600GT include support for Pixel and Vertex Shader 3.0. NVIDIA has coined the term Shader Model 3.0 for the combination. I've covered the major features of the NV4x architecture in various 6800 and 6600 reviews in the past and won't rehash the features in this review. ATI is set to launch a SM3.0 card sometime this year. For now, if you want to get the features SM 3.0 provide, you need a NVIDIA video card.
Two Cards
One feature that I want speak on in this review is SLI. SLI stands for Scalable Link Interface. SLI allows the user to buy one 6600GT and later add another 6600GT to increase performance in games that are supported through NVIDIA's profiles. In some cases the performance can be nearly doubled, but results can vary depending on whether the game is CPU or video card bound. Two modes of SLI are available on NVIDIA's card, SFR and AFR. SFR stands for Single Frame Rendering. In this mode, both cards render part of the screen. AFR stands for Alternate Frame Rendering. In this mode each card renders a frame one after the other.
