Help understanding PCIe 16x/8x/16x/8x
#1
Hi there,

Quite new to designing cracking rig and I'm struggling to understand the impact of having a 16x PCIe slot used at 8x (2 lanes ?).

Most of the motherboard I see (gaming ones) which have 4x PCIe 16x slots use in fact two slots as full 16x slots, and two as 8x slots, thus reducing performance if I'm right.

Am I right saying that a 16x PCIe slot (8x) is slower than a 16x PCIe slot (16x) ?

Is it a problem ? if I want to use 4 rtx 3080, is it a waste of money, and should I use another motherboard with 4 fully 16x PCIe slots (does it even exist in ATX format ?).

I also see many motherboards with nvme ssd using the same lanes as a pcie slot, thus reducing a slot to a 4x or even disabling it. Are there any motherboard in ATX format that I could use with 4 RTX 3080 and at least one nvme SSD, without having to worry about wasting money because a slot is in fact at 15% performance because of beeing an actual 8x pcie slot, reduced to 4x thanks to the nvme ssd ?

Thanks by advance for your help Smile
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Messages In This Thread
Help understanding PCIe 16x/8x/16x/8x - by almandin - 10-28-2020, 06:33 PM