We've seen CrossFire really blossom since the launch of the HD 6000 series with just some insane performance gains being seen from these new single GPU cards. When throwing in a second card we're seeing gains that sometimes equate to almost double the performance. Considering that you can't really expect any more than that, it's really amazing to see AMD really put huge amounts of effort into the improvement of this technology.
Moving to more than two GPUs has never yielded the same performance increases. The HD 5970 as good as a card it was, when you went down the path of two the performance was really quite uneventful. Sure, there were pieces of shining light here and there, but on a whole it was a tough recommendation to go down the four GPU path.
So with all these performance improvements with the latest generation of cards from AMD, how does that translate with the new dual GPU beast from AMD which when in CrossFireX carries with it four GPUs?
With the help of our second HD 6990 from AMD we're going to find out exactly what's going on today. Because it's a reference card, we'll just have a quick look at the card itself as there's no package. Then we'll just quickly run over the specifications.
Of course, you're not really seeing anything here that you didn't see from the Sapphire version with the fan in the middle of the card blowing onto two Vapor Chamber coolers. The card is powered by two 8-Pin PCI-E power connectors and we've got our single CrossFire connector and BIOS switch that enables "AUSUM" mode. Connectivity comes in the form of four mini DisplayPort connectors and a single Dual-Link DVI.
Because our time with this HD 6990 is quite limited and it really has to do the rounds, we thought we'd just crank the card into AUSUM mode which means our core comes in at 880MHz instead of 830MHz which you can see below.
As for the 4GB of RAM, that comes in at 5GHz and the most important piece of information here is the CrossFire tab which shows us that the technology is indeed enabled, and in this case is running 4 GPUs.