The development of new 3D graphics technology is taking some interesting turns. The technology
changes quickly and a new graphics chip can shoot to top position on the 3D leader board, only to be deposed by a new entrant within a matter of weeks or months.
nVidia’s GeForce and GeForce2 GTS chips have dominated recently because they contain an internal transform and lighting (T&L) engine, which takes the processing load for T&L calculations away from the system’s CPU. 3dfx argues that, for the moment, there is not enough support in games and 3D APIs to justify the extra cost of including a T&L engine in its graphics adaptors.
Instead. 3dfx has decided to use two processing chips on the new VoodooS 5500 graphics card, an approach that was also taken by ATI for its Rage Fury MAXX card. The Rage Fury MAXX uses two processors to render alternate frames, but the VoodooS uses a technique called scan line interleave (SLI), which it developed in the Voodoo2 graphics card. SLI uses two processors to render alternate lines within the same frame, and then puts the composite picture together afterwards.
The Voodoo5 5500 features two VSA-100 graphics processors, each with 32M of SGRAM. To fit all this in, the VoodooS 5500 is a very big card, and to power it all, it needs to be hooked directly into the power supply with a spare power cable similar to a hard disk drive. Make sure you have one spare, or buy a double adaptor.
The VSA-100 graphics processor chip (VSA stands for Voodoo Scalable Architecture) is designed to work in multi-chip configurations. It’s scalable in the sense that if more processing is required, more chips can be built into the same graphics adaptor. There are plans for a four-chip version of the VoodooS with 128M of memory.
3dfx says the card can process 366 million pixels per second, or 11 million triangles per second. It has a 350MHz RAMDAC, as do all its current competitors, and a
maximum resolution of 2,048 by 1,536. It can handle textures of up to 2K by 2K and 32-bit colour. As well as supporting the DXTC texture compression used by DirectX, the VoodooS 5500 also uses its own texture compression algorithm called FXT1, which gives an effective compression ratio of 8:1.
Image quality has improved and games now have a more cinematic feel. T-buffer technology allows full scene anti-aliasing (FSAA), spatial anti-aliasing, motion blur and depth of field. 3dfx claims the VSA-100 chip can perform FSAA without a noticeable performance hit. Reviews on game enthusiast sites such as Kick Ass Gear have shown that FSAA can degrade performance quite noticeably at high resolutions.
APC tested the VoodooS 5500 using the same Dell 800MHz Pentium III machine used in the graphics card tests last month (see APC July, page 98). 3dfx recently recalled large batches of the alpha release version of the VoodooS, and based on our test results, it’s not hard to see why.
The performance of the alpha VoodooS 5500 that APC examined was uninspiring, and clearly not up to the standard of its competitor, the GeForce 2 GTS. If compared with the graphics cards we tested last month, it would have fallen somewhere mid-field for most tests. It scored poorly in the video tests, lagging well behind the field In two of the three categories of the Video2000 test. It also scored very poorly In TreeMark, but this benchmark uses very complex polygon figures, and is specifically designed to show off the T&L capabilities of the GeForce.
Hopefully, the alpha card recall will see the VoodooS improve considerably. The current card is hard to recommend.

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