Connecting dual CRTs to two 980s in SLI

rabidz7

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I am thinking of upgrading my monitor to either a FW900 or a Lacie Electron Blue IV. I want to keep my current monitor (Nokia 445Pro) on the side. However, 980s only have one DVI-I port and I am using them in SLI. Is it possible to do this? If so, what adapter would I need?
 
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Looking at this:

http://www.nvidia.in/object/sli-technology-multimonitor-in.html

It seems to suggest that in LSI mode that all monitors are hooked up to the first GPU.

You may have some luck with a passive DP -> 15 pin VGA adapter as it may allow RAMDAC pass-through to get a full spec'd 400 Mhz pixel clock output however I don't think that will work while DVI-I is in use because looking at the linux drivers I only see one CRT-0 output which I know is used for the DVI-I port when an adapter is used:

Code:
(II) Jan 05 21:33:31 NVIDIA(0): NVIDIA GPU GeForce GTX 980 (GM204-A) at PCI:131:0:0 (GPU-0)
(--) Jan 05 21:33:31 NVIDIA(0): Memory: 4194304 kBytes
(--) Jan 05 21:33:31 NVIDIA(0): VideoBIOS: 84.04.1f.00.02
(II) Jan 05 21:33:31 NVIDIA(0): Detected PCI Express Link width: 16X
(--) Jan 05 21:33:31 NVIDIA(0): Valid display device(s) on GeForce GTX 980 at PCI:131:0:0
(--) Jan 05 21:33:31 NVIDIA(0):     CRT-0
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-0
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-1
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-2
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-3
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-4
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-5
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-6
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-7
(--) Jan 05 21:33:31 NVIDIA(0):     DFP-8

Several of the other DFP's are for TMDS pass-through for passive DP -> HDMI/DVI, DVI ports and actual DP ports.

Unfortunately all the active DP -> VGA adpaters appear to have 160 Mhz DAC's which means you won't be able to get much more than 1600x1200 @ 60 Hz using standard GTF timings for a CRT. I found one HDMI -> 15 pin VGA adapter that is a bit higher @ 220 Mhz but even then that is going to limit your refresh rate at higher resolutions significantly.
 

jackstar7

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Wait... what? You hook up one monitor to each card and you should be done.

AMD needs all monitors hooked up to the "master" card, not nV,
 
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I'm not 100%, but I did find this showing one monitor hooked up to each card:

https://www.youtube.com/watch?v=fccuuCHREo4

And I swear I've seen it in multiple reviews... but I've not done it myself.

yet in that video where it shows them on seperate cards it lists that as the 'wrong' setup and then shows a 'right setup' with them both hooked up to the primary card.

Maybe its just a difference of being able to dedicated a card to physX or something or just an effeciency thing.

My memory tells me in the old days this didn't work but I am talking very old days (like pre geforce 400 series days).
 

chili dog

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Don't you have another old monitor with VGA that you can test it with? I know you said in a different thread that you still have an LCD that you keep as a backup.
 

rabidz7

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Don't you have another old monitor with VGA that you can test it with? I know you said in a different thread that you still have an LCD that you keep as a backup.

I just tried that. Looks like this won't work. Both monitors worked with SLI disabled, but only the one attached to the master worked with SLI enabled.
 
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I just tried that. Looks like this won't work. Both monitors worked with SLI disabled, but only the one attached to the master worked with SLI enabled.

Sounds like you are kind of screwed if you want any kind of high resolution/Hz on both monitors while in SLI mode :(
 

dmonkey

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Can't you run integrated graphics alongside SLi on desktops? Enable the HD4000 in bios and plug it into your mobo and see.
 
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Can't you run integrated graphics alongside SLi on desktops? Enable the HD4000 in bios and plug it into your mobo and see.

I was kind of under the assumption he wanted to run 3d over the two displays. If that wasn't the case then why not just get any cheap video card to run the second CRT?
 

rabidz7

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Can't you run integrated graphics alongside SLi on desktops? Enable the HD4000 in bios and plug it into your mobo and see.

I don't use a piece of garbage CPU with integrated graphics... I am using a 4930K.
 

rabidz7

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I was kind of under the assumption he wanted to run 3d over the two displays. If that wasn't the case then why not just get any cheap video card to run the second CRT?

I will probably just hook up the old monitor to a GT210 I have laying around, but I wanted to connect both CRTs to my 980s so that I could play on either monitor, not just one.
 
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