Let's get a brief run-down of the 3D features that the GeForce 256 will posses:
- 15M triangles/sec - sustained DMA, transform/clip/light, setup, rasterize and render rate.
- 4 Pixels per clock (4 pixel pipelines).
- 480M pixels/sec fill rate - 32 texture samples per clock, full speed 8-tap anisotropic filtering.
- 8 hardware lights.
- 350 MHz RAMDAC.
- Most feature complete for DX7 and OGL - Transform & Lighting, Cube environment mapping, projective textures, and texture compression.
- Will utilize 4x AGP performance with Fast Writes, which enables the CPU to send data directly to the GPU (1 GB/sec transfer rate), increasing overall performance and freeing the system memory bus for other functions.
- 256 bit rendering engine.
- Highest quality HDTV (High Definition Television) video playback.
- High Precision HDTV video overlay.
- 5 horizontal, 3 vertical taps.
- 8:1 up/down scaling.
- Independent hue, saturation and brightness controls in hardware.
- High bandwidth HDTV class video I/O.
- 16 bit video port.
- Full host port.
- Dedicated DMA video.
- Powerful HDTV motion compensation.
- Full frame rate DVD to 1080i resolution.
- Full precision subpixel accuracy to 1/16 pixel.
With Intel's imminent release of the Camino (820) chipset on September 27th, expect to see S3, Matrox and 3dfx (whatever happened to Rendition?) to continue to move forward with support for AGP 4X. 3D graphics could certainly go the next step via AGP 4X's capabilities and thus NVIDIA is taking it a step further. When scouring through their white papers on AGP 4X, we noticed that they have designed their own AGP Fast Writes north bridge (per AGP 2.0 spec) and used it as a test vehicle for the GeForce 256 GPU.
With Intel having validated only NVIDIA's Fast Writes thus far, they feel they have the advantage by supporting the 'Fast Write' feature, which is actually a part of the AGP 2.0 specification. It allows the CPU to send data directly to the graphics bus without having to go through system memory (removing a bottleneck) and it also frees up the system memory bus allowing it to perform other functions. Fast Writes improves performance on certain calculations from the CPU to the GPU, which include these four main areas:
- 2D operations
- Operations involving writing data to the frame buffer or sending data to the graphics chip
- Loading textures in D3D into local memory
- Writing push buffers to graphics local memory (should be where the greatest benefit of the benefit will be had).
|