Smoothvision is ATI's newest method of instituting anti-aliasing. The way in which it differs from traditional anti-aliasing is, again falling in with the current trend, to allow programmability. Smoothvision is a multi-sampling AA method, meaning it renders four frames of the same scene then averages out colour values from selected points of each pixel to be Anti-aliased. It allows developers to either program or randomize the pattern of sample points within each pixel. This should lead to more 'natural' looking blending between the edges of a model and the background scene.

As well as the three new technologies, the 8500 chip also offers enhanced versions of several of the original Radeon's flagship features.

HyperZ is a combination of three technologies aimed at conserving memory bandwidth inside the graphics card. Hierarchical Z checks whether each pixel to be rendered will actually be visible in the final frame, referencing the Z-buffer (a memory area which stores the depth, or Z value of each pixel to be rendered) to find the information. What sets this apart from other graphics chipsets is that the Z-buffer check is performed before the pixel is rendered, and pixels that will not be visible are discarded, thus conserving bandwidth. Most graphical chipsets will texture and shade a pixel before checking it against the Z-buffer.

Z-compression compresses the information stored in the Z-buffer, saving more bandwidth, and finally, Fast Z-clear is ATI's method of clearing the z-buffer quickly after a frame has been rendered.

The 8500's HyperZ II is capable of discarding more unnecessary pixels per clock cycle, compressing Z-buffer data more efficiently and generally doing more Hyper Z things... you get the picture. Not overly different, just enhanced for the new chip. Same thing with the Charisma Engine II (nice name...) which is the transform and lighting engine that works along with the Smartshader to draw, manipulate and light triangles prior to rendering.

Pixel Tapestry II is the 8500's pixel rendering engine, and as noted above, has full support for DirectX 8.1 and the ability to draw up to 6 pixels in a single rendering pass.

Other interesting things include support for ATI's Hydravision technology, first seen earlier this year in the Radeon VE. This is a flexible implementation of dual monitor support, with added TV-out ability, allowing dual CRT monitors with independent displays and resolutions, or one CRT and one Digital flat panel display, or a CRT or flat panel plus a TV set. You can also set up the TV as a third monitor, cloning one of the other two displays.

Video Immersion II is a combination of ATI's historically excellent hardware MPEG-2/DVD decoding with improved de-interlacing for video output. This should work hand in hand with the Hydravision feature to allow much higher quality video for DVD viewing and gaming on television sets.

All in all, the Radeon 8500 appears to be a promising competitor for the Geforce3... However a lot of its potential success rests on how software developers take to the new features it offers. Truform could become a standard if it works well, and its ability to be patched into current games means that its adoption could be quite quick. The support for pixel shader 1.4 spec., on the other hand, seems less likely to be a hit. It is unlikely that we will see many games being released specifically for DirectX 8.1 until next year, by which time no doubt the next wave of Nvidia and ATI chips will be almost upon us, making the feature pretty much irrelevant as a selling point.

Without the success of these two technologies, the 8500 will have to go head to head with the GF3 on pure speed alone, which it may well be able to do. A lot will depend on drivers, of course, and ATI has had a few problems in this area before. The 8500 should be released in late September/early October, with the price point apparently set a little bit higher than the average Geforce 3 card's introductory price, but not significantly.