The overall performance analysis looks at the relative performance between all the cards on test across all the settings used in our benchmark suite. For an explanation of our benchmarking procedure, have a look at the descriptions on each test page.
The GTX590 is easily the most powerful card to have gone through our benchmark suite, creeping just ahead of AMD’s HD6990 by less than 1%. Although overall performance is in favour of Nvidia’s dual GPU card in this case, it is still important to note that different games show contrasting results. In Crysis Warhead, Nvidia loses out to AMD and in Far Cry 2 which is generally dominated by Nvidia graphics card, the GTX590 ends up on par with the HD6990. Games that favoured the GTX590 include Resident Evil 5, Street Fighter IV, Unreal Tournament 3, DIRT 2, Batman, HAWX 2, Mafia II and Unigine with extreme tessellation. The surprising observation is whereas the GTX580 easily trumps the HD6970 in the single GPU war, the same cannot be said in the dual GPU race. The fact that AMD’s HD6990 matches the GTX590 may suggest two things; (i) AMD cards scale much better in CrossFire than Nvidia cards in SLI, (ii) the lowered clock speed of the GTX590 has ended up crippling the card. Let’s analyse the first option. Under AUSUM mode, the HD6990 scales by 59% over the single HD6970 and similarly when overclocked, the scaling is by 57.5%. The GTX590 is only 37.71% ahead of the GTX580. Based on the specified fill rates and shader operations which take into account the GTX590s reduced clock speeds, we expected it to be 57% ahead of the GTX590 but instead it is much lower, suggesting less than 100% scaling. Using the same theoretical values as listed in the specifications, two GTX570s in SLI is expected to be 77% ahead of the GTX580 and allowing for the same SLI scaling inefficiencies as the GTX590, the overall performance of the two card setup would still be better than the dual GPU GTX590 for a similar cost. Nonetheless, the GTX590 is still a significant engineering feat and its glory shouldn’t be taken away from it given the fact that it leads the overall performance charts.
Resolution Scaling
The GTX590 is targeted at users gaming on very high resolution displays so it was interesting to see how SLI scaling varied with resolution. As expected, scaling was much better at the higher 1920x1200 resolution where games tend to become more GPU limited rather than CPU limited. An interesting observation is that on games that were not stressful, such as Resident Evil 5, Unreal Tournament 3 and Street Fighter IV, GPU usage fluctuating between the two cores. In those games, GPU usage was around 60% across both GPUs at the lower settings and gradually increased with the added load of higher in-game settings. However, the resolutions we tested were not enough for GPU usage to reach 100%. This was restricted to only those few games. The lower GPU usage may be the reason why SLI scaling was not 100%. On the other hand, it can be argued that the sheer performance experienced in those games don’t warrant the need for the card to operate at its maximum potential in an attempt to reduce power consumption. Afterall, in GPU limited games such as Crysis and Metro2033, GPU usage was always at 100%.
