NVIDIA NF200 x16/x16 vs. Intel x8/x8 P67 Performance Analysis
 

Unlike most performance motherboards that by default carry only an x8 / x8 setup when SLI or CrossFire X is used, the ASUS Maximus IV Extreme offers us the NF200 chip to add more PCI-E lanes to the board. Over the last few years we've seen companies implement the chip to boards to help move the default SLI or CrossFire X setup from x8 / x8 which is offered via the Intel chipset, to x16 / x16 via the NF200 chip.

When you move away from a two card setup and into a three card one, boards without the NF200 chip would run x8 / x8 / x4, while with the NF200 we're able to achieve x16 / x8 / x8 which when having so much power on hand, is extremely appreciated. ASUS do it a little differently, though, and they do it in a way that has confused people. On the Maximus IV Extreme and Extreme-Z, their P67 and Z68 boards, by default they offer x8 / x8 via the Intel chipset. It isn't until you add a third card into the mix that the NF200 chip comes in handy, because in that situation we get a x8 / x16 / x16 setup.

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