We would like to thank the following companies for supplying and supporting us with our test system hardware and equipment: Intel, ASUS and Corsair.

Being an X79 based board means that both HIS video cards are both running at x16 / x16.

When it comes to our graphs today one of the main areas we're going to be looking at is the performance difference between the single HIS HD 7850 iPower IceQ Turbo 4GB and the CrossFire setup we're testing today.

Along with that we've got a couple of higher end single GPU solutions including the new Tahiti LE based HD 7870 from both PowerColor and Sapphire with the latter overclocked. We've also got the PowerColor HD 7950 PCS overclocked and the AMD HD 7970 GHz Edition to round out the collection.

The FPS Numbers Explained

When we benchmark our video cards and look at the graphs, we aim to get to a certain level of FPS which we consider playable. While many may argue that the human eye can't see over 24 FPS or 30 FPS, any true gamer will tell you that as we climb higher in Frames Per Seconds (FPS), the overall gameplay feels smoother. There are three numbers we're looking out for when it comes to our benchmarks.

30 FPS - It's the minimum number we aim for when it comes to games. If you're not dropping below 30 FPS during games, you're going to have a nice and smooth gaming experience. The ideal situation is that even in a heavy fire fight, the minimum stays above 30 FPS making sure that you can continue to aim easily or turn the corner with no dramas.

60 FPS - It's the average we look for when we don't have a minimum coming at us. If we're getting an average of 60 FPS, we should have a minimum of 30 FPS or better and as mentioned above, it means we've got some smooth game play happening.

120 FPS - The new number that we've been hunting down over recent months. If you're the owner of a 120 Hz monitor, to get the most out of it you want to get around the 120 FPS mark. Moving from 60 FPS / 60 Hz to 120 FPS / 120 Hz brings with it a certain fluidity that can't really be explained, but instead has to be experienced. Of course, if you're buying a 120 Hz monitor to take advantage of 3D, an average of 120 FPS in our benchmark means that in 3D you will have an average of 60 FPS, which again means you should expect some smooth gameplay.