PCI-E x1 in a PCI-E x16

[hibby540]

In this thread http://www.tomshardware.com/answers/id-2170871/pcie-card-pcie-x16-slot.html we have someone asking to use a PCI-E x1 in a PCI-E x16. I haven't tried it but I believe that it will work. I have a motherboard with 2x PCI-E slots. When crossfiring the pci-e changes from x16 to x8 and x8. Will a 1x PCI-E card cause the lanes to change proportionate the same way? Or is it proportionate to the amount of lanes?

 

[SkyNetRising]

When crossfiring the pci-e changes from x16 to x8 and x8. Will a 1x PCI-E card cause the lanes to change proportionate the same way? Or is it proportionate to the amount of lanes?

It depends on motherboard. Please list motherboard model name.
Generally, if adding second PCIE graphics card changes configuration to x8 + x8 , then adding x1 PCIE card in same slot, where graphics card would go, does the same thing.

 

[Mark RM]

Yep if it's set to switch to 8x8 to support graphics , adding a x1 adapter there will also cause the 8x8 switch. This is a function on the Intel CPU and that's how it is.

Given that, there are no cards that saturate x8 PCIe 3.0 so what does it matter.

 

[Karadjgne]

Pcie is pcie. All the same sub-system. In an x16 slot, you basically have 4x x4 or 16x x1 slots all joined into 1 long slot. You can even open the end (front) of an x1 slot and install an x16 card.

There's 2x kinds of bandwidth splits. High end boards use x8/x8 split of the 2x pcie x16 slots and a separate buss for the pcie x1 and x4 slots. In the cheaper mobo's you'll see most with x16/x4 and the x4 (still x16 in length) shares bandwidth with the pcie x1_1 slot, so on bios that has to be set for x16/x2 instead.

So yes, you can use the x16 slot for any pcie card, it's the pin settings themselves that just repeat.

 

[hibby540]

This is an MSI 970A Gaming Pro Carbon.

 

[Mark RM]

This is an MSI 970A Gaming Pro Carbon.

supports x16/x0, x8/x8 modes but it's PCIe 2.0 ... still won't bottleneck a video card for the most part.

 

[Karadjgne]

Only the most powerful gpus such as a 1080ti or titan Z/X come close to saturating the bandwidth of pcie 2.0 x8, which is why sli is fine even for those cards. To run 3x cards sli you'd really need to move upto 2011/2011-3 with its higher pcie lane count and x16/x16/x16 instead of the normal x8/x8/x4 on triple x16 lga 115x boards. With pcie 3.0 there isn't a gpu made for commercial use that'll even come close to x8 saturation.