Our previous review of the two most advanced multi-GPU tandems, Nvidia GeForce GTX 480 SLI and Radeon HD 5870 CrossFire, made it clear that Nvidia’s solution is superior to its opponent in most applications. This is no wonder as the GF100 indeed has higher potential than the RV870, and GeForce GTX 480 cards are actually more expensive than Radeon HD 5870s. However, modern multi-GPU technologies are not limited to dual-processor configurations but can be used to combine three or even four graphics cores into a single graphics subsystem. AMD’s technology is more flexible at that. While Nvidia SLI requires two or more identical cards, CrossFire technology allows using different cards, e.g. a Radeon HD 5870 together with a Radeon HD 5850. So, what if we combine a Radeon HD 5870 with a Radeon HD 5970? Such a subsystem would have tremendous potential.
From a theoretical standpoint, Nvidia has nothing to pit against the combined power of 4800 ALUs grouped into 960 superscalar stream processors. In the worst case for AMD, when only one out of each five ALUs has any work to do due to poorly optimized code, AMD’s solution is equal or slightly inferior to Nvidia’s because the GF100 has a higher frequency of the computing subunits. In every other case, the 3-way CrossFire subsystem is far superior to the GeForce GTX 480 SLI tandem, especially in terms of texture-mapping performance. Yes, its practical efficiency is going to be lower than the theoretical expectations due to the synchronization of the Radeon HD 5970 and Radeon HD 5870 working at different clock rates, but even then the performance should be high enough to beat the opponent. That’s what we are going to check out in our tests today.
The foremost drawback of the proposed 3-way CrossFire subsystem is its high price. The Radeon HD 5970 still sells for no less than $650, so the whole configuration can hardly get under $1000 whereas the GeForce GTX 480 tandem easily does that. Anyway, we guess this competition is going to be interesting to fans of both GPU developers.
Besides, we will tell you about a unique version of Radeon HD 5870 offered by Gigabyte. The GV-R587SO-1GD (or Gigabyte Radeon HD 5870 Super Overclock) is going to be interesting for everyone who wants a fast and reliable Radeon HD 5870. This card will serve as the junior part of our 3-way CrossFire subsystem.