Gamers are always interested in how ultra-fast graphics solutions perform even though only few of them eventually buy such products. Catering to our readers’ demands, we have already published two reviews of top-end multi-GPU graphics subsystems. The first review compared ATI’s Radeon HD 4890 CrossFireX with Nvidia’s GeForce GTX 285 SLI. We learned that AMD/ATI’s solution, despite its lower price, is competitive to the pair of more expensive cards from Nvidia in many games and, oddly enough, at high resolutions (1920x1200 and higher).
However, today’s multi-GPU subsystems come in a variety of shapes and are not limited to two GPUs only. As soon as we had acquired a mainboard supporting three Nvidia cards in SLI mode, we pitted against each other 3-way GeForce GTX 285 SLI, 3-way Radeon HD 4890 CrossFireX and 4-way Radeon HD 4870 X2 CrossFireX configurations (see this review for details). The 3-way GeForce GTX 285 SLI came out the overall winner of that test session.
Nvidia also offers a 4-way multi-GPU solution called Quad SLI. This platform has had a long and unlucky history. Its first generation, announced in 2006, made use of specially developed dual-processor GeForce 7900 GX2 cards, and our tests proved that it brought in more problems than benefits. The platform was highly unstable, showed various image artifacts and was occasionally inferior to dual-processor Radeon HD 1900 XT CrossFire and GeForce 7900 GTX SLI in sheer speed. A Quad SLI system based on widely available GeForce 7950 GX2 was free from most of those shortcomings but proved to be slower than a Radeon HD 1950 XTX CrossFire tandem in 12 out of the 20 tests. It was no triumph for Nvidia.
The second-generation Quad SLI, discussed in our There Will Be Speed: The Clash of Modern Multi-GPU Technologies article, was based on unified architecture, but the pair of GeForce 9800 GX2 cards was still unable to win. A pair of Radeon HD 3870 X2 was faster in many games, especially at high resolutions. The lack of multi-monitor configuration support was a downside, too. Such configurations are quite popular among PC enthusiasts.
The release of the GeForce GTX 295 had naturally led to the third generation Quad SLI, but the graphics card itself proved to be too costly. It was actually as costly to make as to be unprofitable for Nvidia. The card did not really take off among wealthy gamers. Its availability was low and we did not have the opportunity to benchmark a configuration with two GeForce GTX 295 cards. The release of the new, single-PCB version of GeForce GTX 295 we have reviewed recently changed this. The simplified design and reduced manufacturing cost can make it popular. Many of Nvidia’s partners have released such products, some of which have already made it to our labs. Thus, we are now able to benchmark a GeForce GTX 295 SLI tandem to ultimately answer the question what multi-GPU subsystem is the fastest of all.
The Quad SLI subsystem will be assembled out of two identical cards: Gainward GTX 295 1792MB and Gigabyte GV-N295-18I-B. Let’s take a closer look at them first.