They have to be Nvidia GeForce cards, natch, but when connected deliver up to 2.8 times the performance of a single GPU. That, the company claimed, is enough to allow games 60fps frame-rates at a resolution of 2560 x 1600 with 8x anti-aliasing enabled.
As expected, 3-way SLI works on systems build upon Nvidia's nForce 680 SLI chipset, and requires three GeForce 8800 GTX or 8800 Ultra cards. A special three-card connector links the three add-in boards.
Oh, and you'll need an 1100W power supply with six six-pin PCIe power connectors... phew"
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