I just received two EVGA RTX 2080s 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"
 
When I go to NVIDIA Control Panel, the SLI option is not present, only the PhysX sub-menu exists.
 
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 - confirmed using NSIGHT, yes I had a 3rd GPU for display. Also, this would not be possible if the PCIe devices were on different roots.
 
Any ideas from the community as to why the NVIDIA Driver is not exposing the SLI option?
 
Thanks, in advance.

Some Motherboards do not support SLI and only support CrossFire.

I don't think it's a lane issue - both are running Gen3 @x16, confirmed this with GPU-Z.
 
@
- I read that, but what does that actually mean? There is nothing on the MB, that I am aware of, that would prevent NVLINK/SLI since data is all going over the bridge. Plus, the other means of GPU communication is over PCIe, and I've already established that they are on the same PCIe topology.
 
@, Since you asked - you wont be impressed:
- Single Intel Xeon E5-1650 V4
- 32GB DDR4
- 480GB SSD HyperX Savage
- HP Z640 Workstation with the HP 710325-002 Motherboard.
-- External 700W PwrSupply dedicated to two GPUs.
-- Stock PwrSupply to drive MB and other peripherals
- Two EVGA NVIDIA  GeForce RTX 2080 XC with EVGA NVLink
 
 

Sounds like you may have a faulty bridge, or one of the nvlink fingers on one the cards is faulty. Time to test the cards and bridge in another pc.

Just a quick response to a few who commented:
@bcavnaugh: I don't have an SLI Bridge for the quadros, unfortunately.
-- I don't see why the BIOS would have anything to do with how the Drivers make use of the PCIe communication or the NVLink Bridge (NVIDIA proprietary).
 
@SprayingMango: Are you saying it's the system HW or the RTX 2080s? 
- FYI: Using the two Quadro P2000s, in TCC, I was able to copy 1GB from one GPU to the other, on average, of 130ms. I did this in both directions, each direction 500 times, back-to-back. That's ~7.5GiBytes per second over PCIe. So the MoBo has no issues with throughput over PCIe - NVLink doesn't even use PCIe (that's the point).
 
@Sajin:
- Maybe you're right; faulty GPUs and/or Bridge.... *ugh*. Or it could be a compatibility issue with the Driver & MoBo *bigger ugh*.
 
For those interested, I did post this question on the NVIDIA forum: [Sorry, for whatever reason the link is being stripped out - just go to NVIDIA GeForce forum and search (same topic title)]

 
If anyone has other suggestions let me know. If I make any progress, I'll update the post.
 
Thanks to all. 
 

normal drivers + nvlink bridge:
 

Then it sounds like you need to go quadro as the 20 series cards don't add up the fb in the new nvlink sli.

@bcavnaugh: I don't have an SLI Bridge for the quadros, unfortunately.
-- I don't see why the BIOS would have anything to do with how the Drivers make use of the PCIe communication or the NVLink Bridge (NVIDIA proprietary).
 
But only that the Bios can impact the Graphics Cards
 
Type: BIOS
Version: 2.46 Rev.A


Operating Systems: Windows 10 (64-bit)  |  [link=javascript:void(0)]View all[/link]
Release date: Sep 12, 2018 File name: sp91925.exe (21.2 MB)
ENHANCEMENTS:
• Improves security of UEFI code and variables. . (Vulnerabilities to be disclosed as HP PSR-2017-0123 and HP PSR-2017-0134). HP strongly recommends promptly transitioning to this updated BIOS version.
• Updates SATA/sSATA UEFI Driver and Option ROM to v4.6.3.1006.
• Updates HP UEFI Diagnostics to v1.21.
• Modifies TPM Activation Policy "No Prompts" WMI setting to also eliminate prompts when upgrading TPM.
• Modifies implementation of ASF port 623 reporting.

PCR0 (TPM 1.2, TXT disabled) = 3864B052A7A5E8D0D68C6B525CE7C264042FFD9C (SHA1)
PCR0 (TPM 1.2, TXT enabled) = A53040199863DE972A57CDCCBA5A1D595B8D622F (SHA1)
PCR0 (TPM 2.0 SHA256, TXT disabled) = 8F6FD3E49706E7EFDAFD56FB55FB8E02FC9766BE482C07D80D8AB2081CF5B196 (SHA256)
PCR0 (TPM 2.0 SHA256, TXT enabled) = B0D9EC8871DABC7D931A6EB0783CDFB3DAA2422F8999301CC4954D1FD2879E77 (SHA256) 
 

-Fixes an issue where system could experience 5 beep error code and fail to boot.
-Fixes an issue where system with AMD graphics and no monitor connected would fail to boot if POST delay is set.
-Fixes an issue where system would appear to hang when attempting to boot with non-bootable media loaded in USB optical drive.
-Fixes an issue where Linux BIOS flash tool (hp-flash) would abort if BIOS Administrator password is set.
-Fixes an issue where Linux BIOS configuration tool (hp-repset) would not return all settings in certain circumstances.
-Fixes an issue where DIMMs would be reported under incorrect processor in Advanced System Information when NUMA mode is disabled. Trusted Execution Technology (TXT) Enabled:
TPM2.0 PCR0 = 069891B9F1AD81ABCFAE52021E0BBC1DC28BDFB0BBEA500F2DE79250EFCD1C34 (SHA256)
TPM1.2 PCR0 = 6BE2BFF25D19294D75F0DE83CA0FB1CDD21F6F99 (SHA1)

Trusted Execution Technology (TXT) Disabled:
TPM2.0 PCR0 = 560FE72389EFA8682594623B6CCEFE4EE5CB4E9C17C4D874479CFE6517CCD6B5 (SHA256)
TPM1.2 PCR0 = DFB0B832FE474457B8EF281CD95FC3DDA8B6C03C (SHA1)
 
Version: 2.34 Rev.A
Fixed in this release:• Fixes an issue where systems with 850W Power Supply would indicate insufficient power with certain high power graphics cards (Z840 only).
• Improves security of UEFI code and variables. HP strongly recommends promptly transitioning to this updated BIOS version.
• Displays warning message for systems where Intel Active Management Technology (AMT) is provisioned and ME FW version is susceptible to escalation of privilege vulnerability (CVE-2017-5689, INTEL-SA-00075).
• Adds ability to boot to a NTFS formatted USB recovery drive.
• Adds thermal support for future Nvidia graphics cards.
• Adds F10 and WMI settings to increase the amount of time allowed for devices to initialize on a cold boot before the first warm reset is issued.
 
 
 
Version: 2.32 Rev.A
Fixed in this release:
• Fixes an issue where microphone would not work after S3 resume.
• Improves acoustics with 32GB DIMMs.
• Updates Intel Memory Reference Code to v4.00.
• Adds Windows SMM Security Mitigations Table (WSMT) support.
• Adds thermal support for multiple future Nvidia and AMD graphics cards.
• Adds support for 32GB DIMMs on Z440.

 
2.38 Rev.A
• Fixes an issue where system would not boot from optical media in certain situations.
• Fixes an issue where system with PCIe cards that do not implement extended config space could hang during POST.
• Fixes an issue where system with certain custom PCIe cards could hang during POST in some slot configurations.
• Fixes an issue where system in Legacy mode with multiple add-in cards could experience PMM allocation error during POST.
• Fixes an issue where Capsule Update would fail with BIOS Administrator Password set.
• Fixes an issue where Network BIOS Update could fail if LAN cable without internet connection is connected to system. • Improves security of UEFI code and variables. . (Vulnerabilities to be disclosed as HP PSR-2017-0123 and HP PSR-2017-0134). HP strongly recommends promptly transitioning to this updated BIOS version.
• Updates SATA/sSATA UEFI Driver and Option ROM to v4.6.3.1006.
• Updates HP UEFI Diagnostics to v1.21.
• Modifies TPM Activation Policy "No Prompts" WMI setting to also eliminate prompts when upgrading TPM.
• Modifies implementation of ASF port 623 reporting.

PCR0 (TPM 1.2, TXT disabled) = 3864B052A7A5E8D0D68C6B525CE7C264042FFD9C (SHA1)
PCR0 (TPM 1.2, TXT enabled) = A53040199863DE972A57CDCCBA5A1D595B8D622F (SHA1)
PCR0 (TPM 2.0 SHA256, TXT disabled) = 8F6FD3E49706E7EFDAFD56FB55FB8E02FC9766BE482C07D80D8AB2081CF5B196 (SHA256)
PCR0 (TPM 2.0 SHA256, TXT enabled) = B0D9EC8871DABC7D931A6EB0783CDFB3DAA2422F8999301CC4954D1FD2879E77 (SHA256)
https://support.hp.com/us-en/drivers/selfservice/hp-z640-workstation/6978835
 

kacan22
I had same problem with NVLink bridge from EVGA ( https://imgur.com/a/vMnMD7k). Check your bridge first then start looking for other solutions.

I do not think anyone would use a Bridge looking like this.
Did you ever test to see if it Worked or not?

kacan22

bcavnaugh

kacan22
I had same problem with NVLink bridge from EVGA ( https://imgur.com/a/vMnMD7k). Check your bridge first then start looking for other solutions.

I do not think anyone would use a Bridge looking like this.
Did you ever test to see if it Worked or not?
 

Green led was working but u cant enable sli. I didnt notice this at all.

Did you RMA it and get a new one?

Looks like quado sli is supported...
 

 
Source: https://www.nvidia.com/ob...-and-motherboards.html
 
But regular sli isn't... https://h30434.www3.hp.co.../highlight/true#M15668

juannunez

Sajin
Looks like quado sli is supported...
 Source: 
 But regular sli isn't... 

Thank you for the references. I am still left wondering why they don't work. I accept the the fact that it wont work - maybe I can work around this with a hacked drivers. However, *why*?
 
What is it about the MoBo that prevents it from working? I am asking to understand and have knowledge. It is one thing to accept the fact. But it is another to want to understand it and learn about it and learn to work with it / around it / find alternatives.
 
I had to learn about PCIe during my adventure. I head to learn about SLI and NVLink and Cuda. I had to learn about Manufacture of Graphics Cards vs Manufacture of the graphics chips. So on and So on.
 
I want to continue to learn and understand why one MoBo is "compatible" while another MoBo is not. Why one MoBo can perform like a Ferrari with Quadros but than same MoBo is no better than a Geo Metro with GeForces.

I posted that in https://forums.evga.com/FindPost/2899479 above as well.

juannunez

Sajin
Looks like quado sli is supported...
 Source: 
 But regular sli isn't... 

Thank you for the references. I am still left wondering why they don't work. I accept the the fact that it wont work - maybe I can work around this with a hacked drivers. However, *why*?
 
What is it about the MoBo that prevents it from working? I am asking to understand and have knowledge. It is one thing to accept the fact. But it is another to want to understand it and learn about it and learn to work with it / around it / find alternatives.
 
I had to learn about PCIe during my adventure. I head to learn about SLI and NVLink and Cuda. I had to learn about Manufacture of Graphics Cards vs Manufacture of the graphics chips. So on and So on.
 
I want to continue to learn and understand why one MoBo is "compatible" while another MoBo is not. Why one MoBo can perform like a Ferrari with Quadros but than same MoBo is no better than a Geo Metro with GeForces.

In your case I believe the reason your motherboard isn't compatible is because nvidia hasn't deemed it certified. Pretty crazy too since your board supports quadro sli. 

And you well not find a setting in the Bios for SLI, no one is saying this.
Updating the Bios provide support for newer hardware on your Motherboard as well as Support for Newer CPUs.
You come here for help and updating the Bios is what is part of helping members.
You are not willing or wanting to update the Bios that is on you.
 
Not sure anyone can help you here, have you asked HP?

Did you give the modded drivers a try yet?