10gbe PCIe not showing up after Blackmagic PCIe card installed.

[Barney-Vidco]

I have a Gigabyte X570 UD motherboard (with 3 x PCIE x16 length slots) and a Mellanox ConnectX-3 10Gbe card. When I install the Decklink card, the 10Gbe card no longer appears in device manager. I have tried switching the slots between the two, but nothing changes. Both cards work perfectly when the other one is not plugged in.
 

• I have tried changing the PCIe Biufication the PCIe Gen settings in the BIOS but that doesn't help.
• I have tried an old Blackmagic Intensity Pro (2009) I had lying around and it works perfectly with the 10gbe card.
• I have also tried an Intel intel X520 10gbe card instead of the Mellanox one, and it doesn't show up if the Decklink card is installed
• I have upgraded the X570 bios firmware to the latest version

I am stumped on this one, hoping someone here might be able to help.

 

 

System:

Ryzen 3800XT

Gigabyte X570 UD Rev1.1

Corsair Vengeance LPX DDR4 3200 MHz- 32GB (2x16)

Gigabyte RTX 3060 12GB

Mellanox ConnectX-3 10Gbe card (also have a intel X520 10Gbe card which I can switch out)

Blackmagic Decklink Studio 4k

 

Windows 10 Pro 21H1 19043.1288

 

 

 

[Windows7ge]

Based on what I'm reading from your motherboards manual all four of the lower slots run through the chipset and that has a finite number of lanes to hand out.

 

Quote

Integrated in the Chipset (PCIEX4/PCIEX1):

• 2 x PCI Express x16 slots, supporting PCIe 4.0 (Note 2)/3.0 and running at x4 (PCIEX4)
• 2 x PCI Express x1 slots, supporting PCIe 4.0 (Note 2)/3.0

 

It doesn't specify that the slots are sharing bandwidth with SATA or M.2 devices but given only 4 lanes go between the CPU & chipset it may not let you run both slots at once.

 

I'd try flipping the cards around and see if the Blackmagic disappears instead of your 10Gig NIC. That would support the theory that you can't use the bottom slot if the middle slot is occupied.

[Barney-Vidco]

1 hour ago, Windows7ge said:

I'd try flipping the cards around and see if the Blackmagic disappears instead of your 10Gig NIC. That would support the theory that you can't use the bottom slot if the middle slot is occupied.

Thanks for your suggestion, I thought this might have been the case too, however, I have already tried flipping the Blackmagic card and the 10gbe and again, only the Blackmagic card shows up. 

[Windows7ge]

11 hours ago, Barney-Vidco said:

Thanks for your suggestion, I thought this might have been the case too, however, I have already tried flipping the Blackmagic card and the 10gbe and again, only the Blackmagic card shows up. 

Is your Mellanox card x4 or x8? I've not heard of it but perhaps Mellanox x8 cards can't run at x4?

 

You did say you had a X520 kicking around yeah?. I'd try that and see if the behaviour changes.

[Barney-Vidco]

8 hours ago, Windows7ge said:

Is your Mellanox card x4 or x8? I've not heard of it but perhaps Mellanox x8 cards can't run at x4?

 

You did say you had a X520 kicking around yeah?. I'd try that and see if the behaviour changes.

Mellanox card is definitely a x4.

 

I have tried the X520 (x8) card, same behaviour.

[Windows7ge]

3 hours ago, Barney-Vidco said:

Mellanox card is definitely a x4.

 

I have tried the X520 (x8) card, same behaviour.

This is going to be a bit of a grasping at straws idea but if you remove the blackmagic card and install both NIC's which appears in device manager?

 

I'm still leaning towards this being a lack of available PCI_e lanes issue but I'd like to see if different cards produce a different behavior.