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The 8800GTX is a video card designed for DirectX 10 that should hit the market early next year with the retail release of the Microsoft Vista Operating System. Games with Pixel Shader 4.0 and Vertex Shader 4.0 functionality will likely hit the market sometime late next year. I'll briefly cover the salient points of the new architecture in this section of the review. The 8800GTX has 128 Stream processors good for doing Pixel Shading, Vertex Shading, Physics Shading, Geometry Shading and more. Each Stream Processor can co-issue a MADD (Multiply+ADD) and MUL (Multiply+Divide) instruction each cycle. The 128 processors are split into 8 clusters of 16 Streaming Processors each. The G80 is a Unified Shader architecture, meaning the 8 clusters are not dedicated to Pixel or Vertex Shading as previous video card architectures (with the exception of the Xenos chip in the Xbox 360). Unified Shaders have the advantage of assigning units to Pixel or Vertex Shading or Geometry Shading as needed instead of a fixed ratio as previous cards had. The GeForce 7900GTX had 24 Pixel Shader Processors, 8 Vertex Shader Processors. If the scene was more vertex laden than pixel laden the performance would suffer as the Pixel Shaders would wait for the Vertex Shader in the scene. Geometry Shaders can create geometry. A primitive is fed into the Geometry Shader and a shape can be output from the GS. Effects that the Geometry Shader can do include Shadow Volumes, Fur, Fins, procedural geometry, graphics card particle systems, displacement effects and programmable vegetation. Anti-Aliasing has been in use on computer video games for years starting with the TNT era. There are two main types of Anti-Aliasing, SuperSample AA and Multisample AA. SSAA up samples the resolution to up to 2x horizontal and 2x vertical resolution. For example 4 sample SSAA on a resolution of 1024x768 would be up sampled to 2048x1536 in 4x mode. Multisample Anti-Aliasing takes several sub-pixel samples of a scene and blends them together.  no AA+no AF  4x AA+16x AF+HDR  8x AA+16x AF+ HDR  8xQ AA+16x AF+ HDR  16x AA+16x AF+HDR  16xQ AA+ 16x AF+ HDR The 8800GTX is capable of single-cycle 4 sample MSAA. Previously, the GeForce 7800GTX was capable of 2x MSAA in a single cycle. The Anti-Aliasing modes the GeForce 8800GTX supports are none, 2x, 4x, 8x (4x AA+4 coverage samples), 8xQ (8x MSAA), 16x (4x MSAA+12 coverage samples), and 16xQ AA (8x MSAA+8 Coverage Samples). Coverage samples are used to determine whether a triangle intersects the coverage sample location. If it does, the CS is used in the final image. If it does not, then the image is taken from the lower sample mode. NVIDIA has been widely criticized for moving to optimizing their Anisotropic Filtering, and rightly so, on the 6800 and 7800 series cards. Personally, I feel that image quality is number one, and would rather have higher IQ than framerate. Angle Independent AF is a pipe dream, true AI AF that is. The amount of samples necessary for true AI AF makes the rendering costs unacceptable for real-time gaming. The 8800GTX has nearly true AI AF, far superior to that of the 7xxx series and better than ATI's HQ AF as well on their X1K series.  no HDR+16xQ AA 16x AF  Bloom+ 16xQ AA+16x AF  HDR+16xQ AA+16x AF The G80 has a new chip called NVIO or NVIDIA Input Output separate from the graphics core. This chip contains the display logic for the 8800GTX. The 8800GTX is the first NVIDIA graphics card capable of displaying 10-bit resolution per color component, instead of the 8-bit that previous cards were capable of. This brings a wider range of colors possible, 1 billion instead of 65,536 in 8-bit. Contents: 
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