PCI EXPRESS X16 Configuration

wam9xx

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Jul 25, 2010
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Hello,
i am building a new computer with core i7-940 processor and P6X58D-E Motherboard. I am going to use a single graphic card and i want to use the Third one (PCIx16-3) slot in order to set free other PCI and PCI Express slots but i m wondering that will it gona be run at full 16X speed or will perform at 8X as mention that
(PCIx16-3)is at 8X speed.... Can i change the speed of this third slot from Bios or is there any other way to do so....
Thanks....
 

lowriderflow

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Yes, will run at x16. The reason it says 3 cards will be at x16x8x8 is because the motherboard only has two bandwidths for the PCI express cards. So if you have two GPU's, they'll both run at x16. However, if you add a 3rd, the 2nd and 3rd have to share one bandwidth (effectively cutting each to x8)
 

socrates047

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Apr 23, 2009
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there is no way to change the width. chipset magic: nothing can be done about it. some premium boards have wider lanes. if yours doesnt have 16/16, only 16/8 or 8/8 or other configs, you can evaluate your needs and maybe benchmark cards in sli/xfire against single to see if you need anything beefier