The arrival of ultra high-end bi-GPU graphics cards from AMD and NVIDIA opens the door for quad GPU systems that are fairly easy to set up, provided, of course, you have the rather big wad of cash you’ll need to invest. We wanted to look at the gains you get from such systems as well as the tri GPU variants, both at high resolution and in surround gaming. Is a quad set-up worth looking at?
What platform for your quad system?
With the GeForce GTX 590 and Radeon HD 6990 you can set up a quad GPU system with just two graphics cards, which simplifies things a good deal in comparison to similar systems based on mono-GPU cards which require a specially designed motherboard.
Although any motherboard with two 16x PCI Express ports can support these systems, in practice it’s a good idea to keep a free slot between the two Radeon HD 6990s or GeForce GTX 590s. This space ensures that cool air can flow into the fan as, in contrast to the GeForce GTX 580s with the beveled back, their efficiency drops significantly when two cards are too close to each other. Ideally, we even advise you to go for a model with two slots between the graphics cards, ie a total of four slots between the PCI Express graphics ports as they’re in double slot format. This was what we had in our tests carried out on the Asus Rampage III Extreme.
You also have to make sure you have an appropriate power supply. With the GeForce GTX 590s in SLI, the Radeon HD 6990s in CrossFire X and the GeForce GTX 580s in 3-way SLI, you’ll need a 1250W model.
Here are the solutions we tested:
GeForce GTX 580
GeForce GTX 580 x2
GeForce GTX 580 x3
GeForce GTX 590
GeForce GTX 590 x2
Radeon HD 6970
Radeon HD 6990
Radeon HD 6990 + Radeon HD 6970
Radeon HD 6990 x2