Windows 10 Pro Device Manager Error with ConnectX-4 Lx Ethernet NIC

So I’m running just two NICs in two PCs which are directly connected via QSFP fiber. I was having throughput issues earlier and upon further review of my BIOS, I noticed I had mistakenly plugged my NIC into a slower PCI 2.0 slot.

However, when I moved the card to my 2nd PCI 4.0 slot (1st PCI 4.0 slot is used by a PCI 3.0x8 graphics card), Windows 10 Pro will initially detect the card BUT once I make any change in advanced settings, I get the following error…Also, if I try to uninstall, Device Manager cannot detect the card in the list for me to reinstall it again. It only comes up again if I reboot my machine.

Note I’m on Silver support but sale went thru on 5/6 or 5/7 so might be why I haven’t come up in the system yet - I was told it takes 10 days to show up


CPU: AMD 16-core Ryzen 9 3950X

Motherboard: MSI MEG X570 UNIFY

Chipset: X570

GPU: Nvidia RTX 2080 SUPER

M.2: PCI Express 4.0 Seagate Firecuda 520

NIC: Mellanox MCX4131A-BCAT ConnectX-4 Lx EN

Hi Andrew,

As you mentioned you have purchased a Silver Support Contract, it would be great if you could confirm your Company Name so we may be able to track the Contract and open a support case.

In the meanwhile, it would be great if you could share the following information:

  1. Is the issue seen on both the PC’s or only one of the 2 connected together?
  2. Is there any other slot to validate if issue follows PCIe slot?
  3. Is it possible to interchange cards in the 2 PCS to validate if issue follows the card?
  4. I believe when you placed the same card in PCIe 2.0 there was not issue related to card not being detected, is this correct?
  5. What is the FW version running on the card?
  6. Could you elaborate which advanced settings did you change for this issue to be triggered?
  7. Could you please share Server details?