It looks like neither of the two new dual-processor graphics cards can claim absolute superiority in games. The Radeon HD 6990 and the GeForce GTX 590 won the same number of my tests and delivered the same performance in the rest of them. We have this equilibrium for two simple but important reasons.
The first reason is that AMD improved its multi-GPU CrossFireX technology in the 6 series GPUs and graphics cards, so it can now often produce a near-100% increase in performance when you add a second Cayman or Barts-based card into your system. As a result, the Radeon HD 68xx and 69xx cards, being slower than the GeForce GTX 560/570/580 in single-card mode, are equal to or even faster than SLI tandems built out of those GeForces. Besides, the Radeon HD 6990 is actually equal to two Radeon HD 6970s and doesn’t differ from them in terms of hardware resources as was the case with AMD’s earlier dual-processor cards. All in all, AMD now has a product whose performance is comparable to that of Nvidia’s dual-processor flagship.
The second reason is that Nvidia seems to have played it too safe, fearing that its new card would be too hot and require too much power. While the GPUs have not been cut down in terms of functional subunits (they are identical to the GTX 580), their frequencies are set much lower and the resulting performance of the GeForce GTX 590 is not as impressive as might be expected. Perhaps Nvidia should have risked releasing this card with clock rates of 750/1500/4000 MHz for example, and this would leave no questions about who’s the leader now. On the other hand, we shouldn’t be upset about that because competition leads to lower prices. At the current moment, these new dual-GPU cards have the same recommended price of $699.
Comparing the new products from other aspects, the GeForce GTX 590 looks somewhat preferable to the Radeon HD 6990 because it is smaller, has a lower temperature of the GPUs (by 10-12°C) and a quieter cooler. But “quieter” doesn’t mean that it’s really quiet because each of these cards is rather noisy in 3D mode. I could not measure the power consumption of the cards for this review but this issue will be covered in our upcoming articles. Stay tuned.