Excerpt: For those seeking no-compromise frame rates on 30-inch LCDs or multi-screen gaming setups, the HD 6990 is today's top-dog card. But you may need a system overhaul to meet its size and power needs.
AMD Radeon HD 6990 4GB graphics card reviewed and rated
8 March 2011
Conclusion: The AMD Radeon HD 6990 4GB is the fastest graphics card in the world. No ifs, no buts, no maybes. Don't even bother considering it if you game at 1,680x1,050. Heck, even a full-HD resolution barely tickles the GPUs. Our testing shows that this card is designed for running many-monitor setups via AMD's Eyefinity technology, perhaps with a 3D cherry on top, because doing otherwise makes little sense.