Before we talk results, lets talk features. The Radeon HD 6990 offers five display outputs: four mini-display ports, and a dual-link DVI port. Every card will ship with 3 adapters (two mini-DisplayPort to DVI, and one mini-DisplayPort to HDMI), for use in an Eyefinity setup. You can drive up to six displays from the card, including arranging five 24-inch screens in portrait mode. Or my personal favorite: driving three 30-inch monitors. If you happen to own, or are considering purchasing three 30-inch displays, a $700 graphics card is likely pocket change (and if you happen to be looking for a roomate, I'm available).

On to the numbers! Our testbed consisted of a Core i7-2600 processor, running at its stock 3.4GHz clock speed, 4GB of RAM, and Windows 7 Home Premium (64-bit). The latest drivers were used for both cards -- in AMD's case, it was a preview version of their Catalyst 11.4 driver.

As always, we'll start with the synthetic benchmarks. First up is Futuremark's 3DMark 11. It's the latest version of the tried and true 3DMark benchmark suite, though 3DMark 11 has been designed for the DirectX 11 era. The benchmark churns through a number of graphics and CPU intensive tests, and then assigns a score based on how the hardware performs.

The numbers speak for themselves. The Radeon HD 6990 boasts a 67% lead over the Nvidia GTX 580 on the Performance setting, sliding up to 70% in Extreme mode.