M.2 NVME SSD won't show up

I just bought this Sabrent PCIE to M.2 SSD adapter card and this Samsung 990 Pro 4TB M.2 NVME SSD, inserted the SSD into the adapter card and the adapter card in the top PCIE 3.0 x8 slot that’s closest to the CPU.


My motherboard is a Supermicro X11SSM-F, which doesn’t have an M.2 slot, so I had to buy the adapter above.
I set BIOS option Advanced > PCIe/PCI/PnP Configuration > NVMe Firmware Source to AMI Native Support but I can’t boot from it and I can’t even find it in the output of command dmesg in TrueNAS Core.

Am I missing something obvious?
Thanks for your help.

If there’s nothing in slot 6 (x16), bifurcation may not work properly for slot 7 (x8).
Try forcing x8x8 bifurcation in BIOS, or move the drive to another slot.

Thanks for your reply!
Actually the adapter has only one M.2 slot, do I still need to enable bifurcation to see that one SSD?

Bifurcation is at board level, slots 6 and 7 share the 16 CPU lanes.

Holy smokes, I finally made it!
Long story short: the issue was the SSD wasn’t properly seated in the adapter socket.
Silly hardware mistakes aside, let me write down some settings that are working for me (not sure if they’re required, though) that might help somebody else in the future:

  • PCIe to M.2 NVME adapter card + SSD in PCIe slot7
  • BIOS:
    • Advanced > Chipet Configuration > System Agent (SA) Configuration > PEG Port Configuration > SLOT7 Bifurcation: [X4X4]
    • Advanced > PCIe/PCI/PnP Configuration > NVMe Firmware Source: AMI Native Support
    • Boot > Hard Disk Drive BBS Priorities > Now NVME SSD shows up in this list. Reorder as needed.
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