building 4x 4090 rig
#6
To be clear, it's not the CPU power/performance that will cause issues. It's the lack of available PCIe lanes. The 14700k only has 20 available lanes. The 13700k is actually the same, give or take on chipset switched lanes(usually for storage devices). You are already not running at x16 on both cards, regardless of what the slots look like. The reason people use threadripper and xeon/epyc CPUs is not because we need the CPU performance necessarily, but because we need the available PCIe lanes. Just because the motherboard has a slot that appears to be x16 physically, does NOT mean that it's connected to x16 lanes electrically. If you want to populate a board with more GPUs, you need to look at how the available lanes will be split up from the CPU/Chipset. A 13700k/14700k can run in x16+x4 with 2 GPUs, which is enough to not notice any major performance losses. Adding more GPUs, however, is either not possible or will require reducing the bus width across all of the GPUs. In THEORY you have enough to give every GPU x4 at least, but I don't know of a motherboard that is setup in a way that allows that right now. Most likely the only configs possible are x8+x4+x1+X1 or siimilar.

The reason Puget is using a threadripper on that board is because it has 128 PCIe lanes available, which is more than enough to provide each GPU with x16. You will not be able to replicate their results on just any motherboard/CPU combo. You would need something that has and exposes enough PCIe lanes for all of your GPUs to get at least x4 lanes to avoid performance issues.
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Messages In This Thread
building 4x 4090 rig - by Siegfried1986 - 05-09-2024, 12:56 PM
RE: building 4x 4090 rig - by Siegfried1986 - 05-09-2024, 01:06 PM
RE: building 4x 4090 rig - by Chick3nman - 05-10-2024, 01:19 AM
RE: building 4x 4090 rig - by Siegfried1986 - 05-13-2024, 05:34 PM
RE: building 4x 4090 rig - by Siegfried1986 - 05-13-2024, 05:36 PM
RE: building 4x 4090 rig - by Chick3nman - 05-13-2024, 07:27 PM
RE: building 4x 4090 rig - by CmdFlaz - 05-14-2024, 11:57 AM
RE: building 4x 4090 rig - by 174region174 - 05-15-2024, 02:00 PM
RE: building 4x 4090 rig - by Sondero - 05-15-2024, 02:27 PM
RE: building 4x 4090 rig - by 174region174 - 05-15-2024, 03:08 PM
RE: building 4x 4090 rig - by Chick3nman - 05-15-2024, 08:13 PM
RE: building 4x 4090 rig - by slyexe - 05-16-2024, 12:23 AM
RE: building 4x 4090 rig - by 174region174 - 05-16-2024, 01:10 PM
RE: building 4x 4090 rig - by Chick3nman - 05-16-2024, 07:49 PM
RE: building 4x 4090 rig - by 174region174 - 05-17-2024, 07:42 AM
RE: building 4x 4090 rig - by Chick3nman - 05-17-2024, 09:31 PM
RE: building 4x 4090 rig - by 174region174 - 05-18-2024, 04:22 PM
RE: building 4x 4090 rig - by Chick3nman - 05-19-2024, 03:31 AM
RE: building 4x 4090 rig - by evilmog - 05-24-2024, 09:35 PM
RE: building 4x 4090 rig - by q6h7jsvdf - 08-15-2024, 07:24 PM
RE: building 4x 4090 rig - by Chick3nman - 08-15-2024, 09:02 PM