STB Velocity 128 ZX

In PC Pro's last graphics card Labs (issue 45), STB produced the second fastest card, the Velocity 128, which was narrowly pipped to the post by the Diamond Viper V330.

Both cards were based around the lightning-fast nVidia Riva 128 chipset, which was the fastest combination 2D and 3D chipset until the Matrox G200 arrived on the scene.

The main limitation of the Riva 128 chipset was that it could only support a maximum 4Mb of SGRAM, which meant that the number of colours it could display at higher resolutions was restricted.

In response to these criticisms, nVidia has released the Riva 128 ZX chipset, which addresses the core problem and can now support up to 8Mb of SGRAM.

The Velocity 128 ZX comes equipped with the maximum complement of 8Mb of SGRAM, but it also uses the AGP interface, so that the main system RAM can be used as a texture buffer.

I ran the Velocity 128 ZX through our gruelling 2D benchmarks, which comprise a set of real-world office tasks running in applications such as Microsoft Word and Access. Disappointingly, the final score was almost identical to that achieved by the standard Velocity 128 and still lags significantly behind the current 2D king, the Matrox Millennium G200. In fact the ZX was fractionally slower than its predecessor although the difference is so small you're unlikely to notice.

A minor but credible improvement is that the refresh rates at higher resolutions have been increased, from 72Hz to 76Hz, resulting in a more comfortable viewing experience.

The 3D functions of the Riva 128 ZX have also been slightly tweaked by nVidia. Direct3D and OpenGL support are both faster and more stable as a result. Running Acclaim's Forsaken using Direct3D produced a very impressive score. At a resolution of 640 x 480, the 128 ZX produced an average of 71.66fps (frames per second), which is noticeably faster than the old Velocity's already impressive score of 66.4fps. At 800 x 600, the performance increased from 49.9fps to 51.5fps - less significant, but still a welcome improvement.

STB has also included an OpenGL driver, which will be useful to those working with high-end graphics applications and for those seeking a touch of out-of-hours office entertainment. Higher resolutions and colour depths can now be supported in 3D, thanks to the additional 4Mb of memory. Whereas the last Velocity 128 was limited to a maximum resolution of 1,024 x 768 in 16-bit colour, the new card can go up to 1,920 x 1,200 in 256 colours.

My only real concern with the 128 ZX was that I had some trouble getting the card to run at a resolution of 800 x 600 in both Direct3D and OpenGL. When I tried switching to this resolution, the signal to the monitor was immediately killed and I ended up having to reboot the system. The problem was solved, however, by switching the resolution from 640 x 480 to 1,024 x 768, and then back down to 800 x 600. Other than that, driver installation was smooth and painless.

Due to time restrictions, we could only evaluate the OEM model of the Velocity 128 ZX. However, there's also a retail model available that includes a significant software bundle. The two main titles are full versions of FIFA 98 and Battlezone, both of which are quality games that will keep most people occupied for some time. In addition to this there are some small 3D utilities such as Wirl - a 3D Web browser - although this is a very basic app.

All in all, the Velocity 128 ZX offers better performance and features than the standard Velocity 128. Although 2D performance remains the same, 3D performance, especially in Direct3D, has been lifted by several frames per second. The addition of an OpenGL driver is another sensible improvement, as it widens the range of professional graphics packages and games that can be run with the card. The additional 4Mb of SGRAM means higher resolutions and colour depths can be supported, while the opportunity for setting higher refresh rates will lead to less eye strain. What's more, the 128 ZX should retail for around £25 less than the previous Velocity 128, which is extremely good value for money.