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There was a lot of hype about the R300 GPU. Now that it's here, you've no doubt heard about how fast it is. Honestly though, speed is a given, but with most videocards post-GeForce 3 having more than enough power, we look for other things to make the purchase worthwhile. Make no mistake though, any post-GF3 video card better be faster also.
Two big headliners are the DirectX 9.0 support and AGP 8x. These are very forward looking features, and you can bet that any cards released in the next 6 months will tout these features as well. Granted, the SiS Xabre was probably the first AGP 8x part on the market, but it's lack of raw horsepower won't make it in the enthusiast market. Returning is Smartshader 2.0, ATi's 2nd generation T&L engine, which includes programmable vertex and pixel shader technologies.
Smoothvision gets an upgrade with Smoothvison 2.0. As the name implies, you get advanced full-scene anti-aliasing (FSAA) and anisotropic filtering. Both these features have been here before, but now everything is done both better and faster.
Anisotropic filtering sharpens textures by removing the blur we're accustomed to seeing in 3D games. With the R300, up to 16 texture samples per pixel can be taken now, though you will suffer a performance hit.
For FSAA, there are two methods. The first is super sampling where as the name implies, the image is rendered at a higher resolution, then filtered down to the display resolution. Jittering, a technique used earlier where multiple offset samples are taken of an image to create a more natural AA, returns again, but at a less performance cost. This is achieved by a lossless compression technique that can be as much as 6 times faster than before.
Truform makes a comeback, and is a technique used to smooth curved surfaces of an object. Using tessellation, a method of increasing polygon count, it is no longer bound by pre-programmed tessellation levels, but rather, it is more flexible and supports continuous tessellation. Depending on the distance from the object, adaptive tessellation comes into play which will adjust the level depending how close you are.
Truform also supports displacement mapping, which provides more control over a 3D object than bump mapping. By adjusting values in the vertices, objects will appear more realistic.
HyperZ III is ATi's method for saving on memory bandwidth. One reason why there is so much fast memory on videocards is because textures, and colour depth eats up a lot of bandwidth. Now on its 3rd generation, HyperZ improves with three different components.
The first is Hierarchical Z, which hides pixels that won't be displayed in a 3D image. The second is Z Compression, which can compress data going to the Z buffer by a 2:1 ratio, and under ideal circumstances 4:1. What is interesting is that with anti-aliasing, it can be as high as 24:1, which should provide a substantial speed benefit for AA performance. Finally, Fast Z Clear clears the Z buffer between rendered frames. At high resolutions, waiting for the Z buffer to clear can take a long time since it requires a large amount of data (7.7MB at 1600x1200) must be written to every frame to clear it. Hyper Z needs just a fraction of the same data, making it much faster.
 
To show that the Radeon is more than games, ATi has introduced the Videoshader. To me, this is more beneficial for those without good broadband connections. What this technology is supposed to do is help smoothout streaming video, which tends to be blocky. The result are clearer and smoother video. For those with captured video, the Videoshader can also clean up the noise that may be present.
It's really a do everything technology, as we can see above. It will be interesting to see how this innovation all plays out as the applications get released that can actually take advantage of it. Let's take a closer look at the card itself...
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