Installing SLI 8/8-- can't skip a slot?

[ArcaneBlades]

Forgive my lack of understanding but as I can tell, you have to use the top two PCIE slots for x8/x8 else you get 16x/4x. Cards overheat, is there anything I just am missing here? Every youtube video I have looked at skipped a PCIE slot (unless it isn't a PCIE slot...). Don't most cards require you to sacrifice a slot anyway?

Are most ppl knowingly running at 16/4? I get that PCIE 3.0 x8 might be just as fast hence maybe I want x8/x8 though the performance was minimal vs 16.

I look at mobo pictures and can't be sure I know what I'm talking about. My history is AGP then gaming laptop with MXM and crossfire then this SLI project is my first experience with PCIE. So I don't know what slots are PCIE and what rate they operate at.

http://www.asrock.com/mb/Intel/Fatal1ty Z77 Professional/#AnglePhoto
Is it the red and black or do I want red and red ports? And how do I get them to run at 8x if not 16x? I will buy a different mobo if it would help me use missing a port as a cooling technique. I just like the polling rate gimmick.

I am interested in the ASRock Fatal1ty Z77 Professional just to play around with hardware that tries to run higher polling rates on a different level. It's more difficult now to overclock your polling rate and it also keeps your other usb hardware from theoretically not functioning so well.

 

[BrightCandle]

Every motherboard is a different. If you take a look in the manual of the motherboard you will find out what its suggested config is for dual cards.

 

[Kenmitch]

On the board in question you'd want to use the upper two red slots. They are pci-e 3.0 and would run your cards at 8x/8x. The lowest is pci-e 2.0 4x only and would be used for something like a dedicated physx card or controller card.

 

[Wall Street]

Any GPU can run in any PCIe port, there is no magic surrounding the position of the first, second or third port and so on. However, the Ivy Bridge chip only offers 16 lanes of PCIe on the CPU with 8 lanes of PCIe 2.0 from the chipset. Therefore, the motherboard makers have to choose which two slots get 8 lanes of 3.0 and which get the 4 lanes from the chipset. Obviously, you need to research the motherboards you are looking at and decide if you want one with the fast lanes two or three slots apart.