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+--- Thread: Are two CPU's required for a 6-8 GPU rig? (/thread-8356.html)
Are two CPU's required for a 6-8 GPU rig? - dontknowmuch - 05-14-2019
Hey friends.
My company wants to purchase a 6 GPU rig with an option for 8.
Our IT guy says that for a 4+ GPU rig, it is a must to have two CPUs, and maybe more for an 8 GPU build.
I've never heard of that, is there any truth to that?
RE: Are two CPU's required for a 6-8 GPU rig? - Chick3nman - 05-14-2019
Yes and No. In theory 2 CPUs provide more PCI-E lanes so more GPUs can run with proper bandwidth. But they are not required assuming the board you choose has a backplane with PLX chips on it, which switch the pci-e lanes to the GPUs in such a way that it can run several GPUs with fewer PCI-E lanes. I've heard of as high as 32 cards connected to a single 2x CPU board. And at least 18 on a single CPU board.
RE: Are two CPU's required for a 6-8 GPU rig? - dontknowmuch - 05-15-2019
(05-14-2019, 10:09 PM)Chick3nman Wrote: Yes and No. In theory 2 CPUs provide more PCI-E lanes so more GPUs can run with proper bandwidth. But they are not required assuming the board you choose has a backplane with PLX chips on it, which switch the pci-e lanes to the GPUs in such a way that it can run several GPUs with fewer PCI-E lanes. I've heard of as high as 32 cards connected to a single 2x CPU board. And at least 18 on a single CPU board.
that is fantastic information.
is there any way of knowing if the board has a backplane with PLX chips? all i know is that the server will be a ESC8000 G4 Intel 2*Socket P(LGA 3647)CP 8*2.5 4U.
thank you
RE: Are two CPU's required for a 6-8 GPU rig? - lapwing - 05-15-2019
According to the website the ESC8000 supports a single root complex (one CPU) with all PCI slots connected through two PCIe switches. (Scroll down to "Patented Adaptable Topology design")
Enjoy
RE: Are two CPU's required for a 6-8 GPU rig? - dontknowmuch - 05-15-2019
(05-15-2019, 07:20 PM)lapwing Wrote: According to the website the ESC8000 supports a single root complex (one CPU) with all PCI slots connected through two PCIe switches. (Scroll down to "Patented Adaptable Topology design")
Enjoy
Wow, i have no idea what you said, buy i take it as a -i think it should work with 1cpu on 8 cpu"