Six Screens on 2x RTX 2080 Super

Hi All,

Hope all is going good for everybody - I wonder if I can get some guidance on setting up my Ubuntu 20.04 install with the 6 monitors and 2 gpu’s.

Unlike in Windows, I do not have the option to enable all screens within the GUI config tool - the best I can see using the nvidia-config tool is a pretty useless second X display which I can’t find a way to integrate into the desktop.

I’ve tried quite a few approaches to this now but does anybody know what is the correct approach?

Thank you,
Paul

Might work with the upcoming 450 driver. Having two rtx 2080 for graphics is pointless, though. May I ask what lead to the decision?

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Hi Generix,

Are you confirming that there’s no way to get it working with the current drivers? Both cards are recognised by the system and I can have the second card’s screens form a secondary x display (although this is largely useless). All six work flawlessly on windows with SLI disabled…

To the second point - enough grunt to drive 6x 4k screens and run hashcat with a decent rate.

Cheers,
P.

GPU graphics performance doesn’t add up simply by plugging a second (third, fourth) one into the system. Only useful for compute jobs.
Nvidia Mosaic on Linux has been nerfed down to three monitors on consumer Geforce cards, more only working on Quadros.
The only way currently to have this is to enable Xinerama but then composition has to be turned off so stock Ubuntu won’t work since Gnome doesn’t work without compositing. So you would have to switch to KDE/XFCE or the like.
Like said, another option might come with the upcoming 450 driver’s outputsink feature but it’s still unknown how this will actually work out with dual nvidia gpus.

Hi Generix,

Thank you for your response - well obviously I agree with your first statement, who wouldn’t!

It is a shame about the 3 monitor limit, what a waste.

Xinerama didn’t work for me and it’s pretty rubbish from experience anyway so I’ll just switch my plans around and use windows for the main/host OS and just have linux in a vm.

Thankfully, the cuda/compute job software I wanted to run in linux has a windows equivalent so I don’t lose much.

Cheers for your help - by the way are you an nvidia representative or member of the public?

Thank you,
Paul

I’m just an ordinary user, nvidia staff has green posts and nvidia logo.

@generix
You are the beating heart of this forum! ;-)
Can’t (or don’t want to) imagine, how it would be here without you.

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This has been a problem for a LONG while. I have worked to get a 3x2 setup for about 3 card generations now (went as far as to buy 2 @ P2000s - which didn’t help -as they can’t be bridged). So now I am settling for 4x outputs with it until we get a driver that will push 6 screens. Disappointed in Nvidia but it is what it is.

Matthew

Though on Quadros this is a supported (and advertised) feature so should work. Did you check if just the mainboard is blocking inter-gpu communication by disabling iommu?