SLI is limited to two graphics cards, but Gigabyte is working towards raising that limit ...Gigabyte's innovation in the graphics department lead to a GeForce 6600GT with dual GPUs, internally linked through NVIDIA's SLI interface. We reviewed that card here. The moment we first laid our eyes upon the creation, our first thoughts were "Can we shove two of these into an SLI board to get four GPUs?". Invariably, the answer was "no", but Gigabyte has made some inroads in that respect, and they already have a board.
Gigabyte's GA-8N-SLI Quad actually supports four NVIDIA SLI graphics cards, or four GPUs (as in, two dual-GPU cards). There is no word on how you would go about linking four cards, but they must have figured out a way. They've managed to get this done by using two nForce 4 chipsets (I assume to provide the extra PCIe lanes required).
You thought people were crazy to spend the bucks on two 6800's ... prepare to be amazed.
Article Link: Gigabyte to support four SLI graphics cards on one motherboard
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