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Threadripper PCIE root complex inquiry

Question asked by rippr on Apr 24, 2018

I wanted to inquiry as to how many PCIE Root complexes the thread ripper (1950x) has?

Correct me if I'm wrong but my understanding is that it has two (one for each die)?
That being said, will this cause an issue with Nvidia's GPU Direct if I have the cards in slots assigned to different dies?
What kind of issue might I face for a pcie card plugged into the PCIE 2.0 x1 slot that has to traverse the chipset in a particular root complex?

GPU Direct : For GPUDirect RDMA to work between a third-party device and an NVIDIA GPU they must share the same root complex

Is there documentation where AMD defines the PCIE root complex structure for threadripper?

What confuses me at the moment is the output of lspci -tv which seems to indicate two root branches. I have video cards on each branch in the x16 slots. Under lspci, they reside off of two distinct branches. However, when I execute a deviceQuery on my cards it shows they are both in pciDomainID : 0 with different bus IDs and the same PCIdeviceID.

If someone could answer this as soon as possible, I'd greatly appreciate it. I need to make a costly purchase by the end of the week that's dependent on this answer.
Also, I'd appreciate as much detail as possible


My analysis so far is that one complex has :
x16/x8/x4 nvme/x4 nvme

While the other has :
x16/x8/x4 nvme/x4 chipset
Is this correct?