Question Unable to Get SLI/NVlink Working with my x2 EVGA GTX 2080 SUPER XC ULTRAs

[mrshaggydoo]

Hello! Thanks for reading.


Specs:

PCPartPicker Part List

CPU: AMD Ryzen 9 3950X 3.5 GHz 16-Core Processor ($709.99 @ Amazon)
CPU Cooler: Noctua NH-C14S 82.52 CFM CPU Cooler ($74.90 @ Amazon)
Motherboard: MSI MEG X570 UNIFY ATX AM4 Motherboard ($299.99 @ B&H)
Memory: G.Skill Trident Z RGB 64 GB (4 x 16 GB) DDR4-3000 CL16 Memory ($324.08 @ Amazon)
Storage: Samsung 970 Evo 1 TB M.2-2280 NVME Solid State Drive ($167.00 @ Amazon)
Storage: Samsung 970 Evo 1 TB M.2-2280 NVME Solid State Drive ($167.00 @ Amazon)
Video Card: EVGA GeForce RTX 2080 SUPER 8 GB XC ULTRA GAMING Video Card (2-Way SLI) ($999.99 @ Amazon)
Video Card: EVGA GeForce RTX 2080 SUPER 8 GB XC ULTRA GAMING Video Card (2-Way SLI) ($999.99 @ Amazon)
Case: be quiet! Dark Base Pro 900 Rev. 2 ATX Full Tower Case ($249.97 @ Amazon)
Power Supply: EVGA SuperNOVA P2 1200 W 80+ Platinum Certified Fully Modular ATX Power Supply ($310.99 @ Amazon)
Operating System: *Microsoft Windows 10 Pro OEM 64-bit ($139.88 @ Other World Computing)
Generated by PCPartPicker 2020-08-24 23:14 EDT-0400

AND
I just got this in the mail today (I bought it directly from nvidia, not this site): https://www.avadirect.com/GeForce-R...ng-60-96mm-For-RTX-20-Series/Product/12294592
for the bridge between them. I can't for the life of me find a full database of which one to use. As I'm typing this I'm think I may have bought the wrong one.


The problem is....

I have these two cards I'm trying to get to have the SLI work, but they do not show up in the device manager, on GPU-Z, or in the Nvidia system settings. The two cards show up in the BIOS as having independent temperatures (more about the bios in the picture section), and I have switched their order and tried each one independently. The NVlink LED comes on, and both GFX card lights come on as well.

Photo of it not working:

https://imgur.com/a/hhV3Zak

View: https://imgur.com/a/hhV3Zak


Various system screenshots:

https://imgur.com/a/yI0jNkL

View: https://imgur.com/a/yI0jNkL


I've tried...

Updated bios
installed dragon center and updated drivers
re-installed windows 10
CMOS button
changing lanes from Auto to x8 x8 in bios,
safe mode DDU and reinstalled x4+ times with different configs from bios.

Note about the BIOS config

BIOS are acting very weird. I have one card showing up under board explorer when the PCI-E Lane setting is set to "auto" and when I set it to x8 - x8 I get only the second card being active. Album with descriptions here:

https://imgur.com/a/xwp6FuJ

View: https://imgur.com/a/xwp6FuJ


last thought

As I finish this post I'm thinking I should have bought the NVlink bridge that matches the brand of the cards. I.E this one exactly: https://www.amazon.com/EVGA-GeForce-Bridge-Spacing-100-2W-0029-LR/dp/B07HZFTNFQ
What are you guys' thoughts on all this? Thanks in advance!

 

[mrshaggydoo]

Thanks for all the replies! I called MSI and I have made the conclusion it is a bad PCI-E 3 Slot.
Doing an RMA on the MOBO. Will report back.

 

[mrshaggydoo]

Plugged in new MOBO. Was able to see the two cards without windows installed on board explorer. both were red. I was stoked!

I installed windows and the drivers, and I had to take out one of the cards here and put it back in to get in a fix a loose connection with the SSD's underneath them. Then it went right back to doing what it was doing before. Totally different motherboard...is it the graphics cards? They were refurbished. But they both seem to be working.

I tried flashing older versions of the x570 chipset bios but nothing. I even removed all my harddrives to see if I could get it without windows being installed. Nothing.

is it the PCI-E lanes? My mobo only has x16 and x8 dedicated for graphics cards on those PCI slots. Iono I'm getting kind of desperate for answers here.