PCIe Lanes Question

stahlhart

Super Moderator Graphics Cards
Dec 21, 2010
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Here is a portion of the specifications for the Gigabyte GA-PA67A-UD4:

  1. 1 x PCI Express x16 slot, running at x16 (PCIEX16)
    * For optimum performance, if only one PCI Express graphics card is to be installed, be sure to install it in the PCIEX16 slot.
  2. 1 x PCI Express x16 slot, running at x8 (PCIEX8) * The PCIEX8 slot shares bandwidth with the PCIEX16 slot. When the PCIEX8 slot is populated, the PCIEX16 slot will operate at up to x8 mode.
  3. 3 x PCI Express x1 slots
    (All PCI Express slots conform to PCI Express 2.0 standard.)
  4. 2 x PCI slots
If you either have one GPU in the X16 slot, or get a second GPU and do SLI or CF, running them at X8 and X8, does installing a 1X card have any effect/impact? The specifications don't mention shared bandwidth for the 1X slots -- but aren't there a total of 16, which would be all used up by either the one or the two GPUs, and if so, where are the 1X slots getting their lanes?
 

tcsenter

Lifer
Sep 7, 2001
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If you either have one GPU in the X16 slot, or get a second GPU and do SLI or CF, running them at X8 and X8, does installing a 1X card have any effect/impact?
It shouldn't unless the specs indicate otherwise. The P67 has enough peripheral PCI-E x1 lanes via the NB and SB to support three PCI-E x1 slots independent of the x16 PEG slots.
 

stahlhart

Super Moderator Graphics Cards
Dec 21, 2010
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It shouldn't unless the specs indicate otherwise. The P67 has enough peripheral PCI-E x1 lanes via the NB and SB to support three PCI-E x1 slots independent of the x16 PEG slots.

Great; thanks much...