Tested-working Sapphire Radeon HD 5870 Eyefinity6 Edition, 2GB GDDR5. It won Popular Science's 2010 "Best of What's New" award. Specs: 1600 stream processors, 850MHz core, 2GB GDDR5 (256-bit, 153.6GB/s), 40nm TeraScale 2, PCIe 2.1 x16, dual-slot, requires 6-pin + 6-pin PCIe power.
