No NVLink (SLI) Option in Control Panel - RTX 2080 XC

[One-Knee-Toe]

Scenario:

• I just received two EVGA RTX 2080 XCs and the EVGA NVLink bridge.
• I installed both of them on the two PCIe3 X16 slots I have available (confirmed using GPU-Z).
• I installed the NVLink bridge.
• I updated Windows 10 to 1809 (Enterprise, 64bit, LTSC 2019, Build 17763.107).
• I installed the latest NVIDIA Driver (417.35) - did "Clean Install".

Issue: 

• When I go to NVIDIA Control Panel, the SLI option is not present, only the PhysX sub-menu exists.

Extra Info:

• Physically, I know both PCIe Slots are a part of the same PCIe root complex.
• I am able to run two Quadro P2000s in TCC and perform direct (dev-to-dev) cudaMemcpys.
• I confirmed Dev2Dev using NSIGHT; I had a 3rd GPU for display.
• Dev2Dev would not be possible if the PCIe devices were on different roots.

Question/Request: 

• Any ideas from the community as to why the NVIDIA Driver is not exposing the SLI option?

System:

• Single Intel Xeon E5-1650 V4.
• 32GB DDR4.
• 480GB SSD HyperX Savage.
• HP Z640 Workstation with the HP 710325-002 Motherboard.
• HPs Spec Sheet: http://www8.hp.com/h20195/v2/GetPDF.aspx/c04400040.pdf
• External 700W PwrSupply dedicated to the two GPUs.
• Stock PwrSupply to drive MB and other peripherals.
• Two EVGA NVIDIA GeForce RTX 2080 XC with EVGA NVLink.

Thank you, in advance.

[Crunchy Dragon]

Reading through the manual you linked, it appears that the board does not fully support the newer cards, much less two of them.

[One-Knee-Toe]

Forgive the very stupid question - what does that mean, doesn't support?

* Both cards are plugged into the two x16 Gen3 PCIe slots.

* I have an external PSU (700W) dedicated to powering these two GPUs.

 

Is there something more about the MB that is needed?

 

[One-Knee-Toe]

See Attached:

• The HP Spec on the MoBo topology also correlate with my tests with Two Quadro P2000s.
• The Intel CPU Specs also show that the CPU has the dedicated lanes to support two x16 PCIe devices.

[-rascal-]

4 minutes ago, One-Knee-Toe said:

Forgive the very stupid question - what does that mean, doesn't support?

* Both cards are plugged into the two x16 Gen3 PCIe slots.

* I have an external PSU (700W) dedicated to powering these two GPUs.

 

Is there something more about the MB that is needed?

 

 

It looks like the motherboard's firmware / BIOS does not support SLI for nVidia GeForce GPUs.

I am assuming the motherboard physically support multi-GPU SLI, though, since they do offer two GPU set-ups for the Quadro GPUs.