Performance Summary Diagrams
The first pair of summary diagrams shows the advantage of the VTX3D Radeon HD 6970 X-Edition overclocked to 940/5700 MHz over the reference AMD Radeon HD 6970 (880/5500 MHz):
With the GPU and memory clock rates increased by 6.8% and 3.6%, respectively, over those of the reference Radeon HD 6970, the VXT3D card proves to be 4 to 4.5% faster in the lower-quality mode and 3.4 to 4% faster in the FSAA mode. The MSI card overclocked to the same GPU frequency delivered almost the same results through most of the tests because memory frequency is less important for such top-end graphics cards.
The second pair of summary diagrams illustrates the efficiency of CrossFireX technology. We compare a CrossFireX tandem built out of two Radeon HD 6970s clocked at 940/5700 MHz to a single such card clocked at the same frequencies.
CrossFireX is not very efficient or the CrossFireX tandem is limited by the CPU in such games as Borderlands, Warhammer 40 000 Dawn of War II: Retribution, and in the FSAA-less mode of S.T.A.L.K.E.R.: Call of Pripyat and StarCraft 2: Wings of Liberty. But in games like Aliens vs. Predator (2010), Total War: Shogun 2, Just Cause 2, Tom Clancy’s H.A.W.X. 2 and DiRT 3 CrossFireX proves to be as efficient as 90% and higher. The average across the games we’ve tested it in is 67-75% in the lower-quality mode and 78-81% in the 8x/4x MSAA mode.
We measured the power consumption of systems with different graphics cards (without the monitor) using a specially modified power supply. A gaming load was emulated by running Aliens vs. Predator (2010) at 2560x1600 with 16x anisotropic filtering and 4x MSAA. For the maximum load we launched FurMark 1.9.0 in the stability check mode at 2560x1600 with 16x AF and 4x MSAA together with Linpack x64 (LinX 0.6.4, 4750 MB, 5 threads). These two programs load heavily the graphics card and CPU, respectively, so we can determine the peak power draw of the whole system and see what power supply will suffice for it. You can see the results in the diagram:
A 550-watt power supply is going to be sufficient for a system with one Radeon HD 6970 under typical gaming loads. A CrossFireX tandem built out of two such cards will call for a 750-watt or better power supply. And if you are going to put your graphics subsystem under stress loads, the power supply requirements get even stricter: 650 watts for the single card and 900 watts for the CrossFireX tandem. Comparing the three different Radeon HD 6970s, the system with our MSI Radeon R6970 Lightning has the highest power consumption whereas the system with the VTX3D Radeon HD 6970 X-Edition, despite its higher clock rates, needs somewhat less power and is comparable to the system with the reference 6970 in this respect.