Installing 2 NVLinks

[basicnature]

Hi All,

Official word from Nvidia is that this isn't possible. They say only 1 bridge will work in each machine.

Bringing this up because everyone has been assuming that we can all install more than one in a multi-Gpu setup.

I'm wondering if there has been any update on this. I've been able to successfully install one bridge, but every time I try to install a second bridge the Nvidia drivers completely die and I have to reinstall everything. I've heard of people installing 2 links in the same machine? I've been trying this with two Quadro Rtx HB bridges.

Looking to do 4x2080tis with 2 bridges to create 2 pairs of Gpus.

Has anyone here successfully done it and know for a fact how this is accomplished? Seems strange that Nvidia wouldn't allow this in their software, as it makes NVLink useless for any professional with more than 2 Gpus.

Thanks!

[Nejc Kilar]

I don't have an answer for you and I'd like to bump this topic.

That being said, regarding your comment on the NVLink being useless... Yeah, product segmentation potentially. Quadros for professional use (No NVLink limitations) and Geforce for gaming (1x NVLink). Unfortunately it sounds realistic that they'd pull something like that off. That being said, I've also seen 4x Geforce NVLink in action a couple of months ago

[basicnature]

Actually the Quadros have the same limitations too. I've continued speaking with Nvidia and here's what they said. -

"Even with the Quadro RTX 6000, you can have only one SLI set up with a pair of Quadro RTX 6000 cards. It may not be possible to set up a second SLI with another pair of RTX 6000 cards."

[danio]

I thought that dual NVlinks were possible with earlier drivers even on 2080 Ti’s? And then they crippled the drivers. Can anyone speak to this?

[Muhammed_Hamed]

It is possible,
check out this post here,
https://www.facebook.com/groups/Octa...5531279957281/

[basicnature]

UPDATE - I made two NVLink bridges work

A lot of experimenting and failed attempts, but I finally got it working (even though Nvidia still says it's not possible). I installed the first one and got that to work. After that, I put the second bridge in and plugged a dummy HDMI plug into it and tried activating that one. This would not work with monitors plugged into the different linked groups (one monitor in link 1 and the other monitor in link 2) but only worked with the dummy plug. Using the newest drivers - 419.67 and everything seems stable so far. Though NVLink does slow the renders down, just as everyone else has reported.

I can't speak as to whether they used to allow it, but at least this tricks the system in to making it work... for the time being.

Mobo - AsRock z270 Supercarrier
4x2080tis internal w/ 2 Nvlink bridges, 2xTitan Rtx external
Using the Quadro Rtx HB bridges

Hopefully this info will help some people out there.

----------

AnthonyFurlong.com
Insta - @anthonyfurl

[basicnature]

It is possible,
check out this post here,
https://www.facebook.com/groups/Octa...5531279957281/

Ha! You beat me to posting it here. Thanks for helping to spread the word. Trying to help as many people as I can.

[Muhammed_Hamed]

Thanks for all info!
This is gonna be very helpful buying new hardware for many people including me

[duckfukker]

But having two pairs, you still can't render a scene that requires more than 22gb (in the case of 2x2080ti) or have i understood that incorrectly? So what is the point then of having two SLI?

[Muhammed_Hamed]

duckfukker You are correct!
having 2 cards won't cut it for some people speed wise. 4 cards or more might be needed
And having more than 2 cards, you would want the same 22 GB limit so you need to use NVlinked pairs
Nice name as well )

[MANUEL_MOUSIOL]

I'm still waiting for an official answer to my inquiry from nvidia about support for nvlinked pairs. I asked them about it around three weeks ago and the said they will answer up to 48 hours...
I'd love to get two more 2080tis but don't want to base my business on a hack, so to speak...

[MANUEL_MOUSIOL]

So I finally got my answer from nvidia and it's still officially not supported to use the 2x2 setup. And they have no plans to change that.
does anybody have experience with the technique mentioned? Is it stable? Will it hold up even after updating the driver?