Using old 2nd GPU for powering dual Monitors. Beneficial? Drivers?
Learning3D
Posts: 90
Hi friends, currently I am using a single RTX2080TI. While browsing the internet, using dual monitors, 1GB of VRAM is being used.
- So I am thinking if it makes sense to buy a GTX970. I could get it used for about 80€ to drive my monitors.
- Actually I have a GTX570 (1.3GB VRAM) laying around, I could use that as well. I guess no need to get a GTX970? I am afraid that the GTX570 could be to old for running the OS nowadays. Is anybody using such an older card for running the OS? Are there any problems?
Also, how does it work with the drivers since these are different GPUs I need different drivers. How does that work? I simply go to the Nvidia page as usual and download the GTX570 drivers and install them. So I have both the 2080TI and 570 drivers?
---
- My power supply is strong enough. I have enough ventilation and sufficient PCI-E lanes. Anything else I need to think about?
EDIT: I did read the various multi GPU threads in the DAZ forum and many questions were answered. But I couldn't find answers to these questions. I know that the GTX570 will not be used for rendering, because it has not sufficient VRAM for my scenes. But I hope that larger scenes will fit on the RTX2080ti because, hopefully, that 1GB Vram that is currently used for the monitors/OS will be free.
EDIT2: Btw I got inspired through this article: "Adding an old GPU increased my render speed by 24%"
Daz 3D is part of 
Connect
DAZ Productions, Inc.
7533 S Center View Ct #4664
West Jordan, UT 84084
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2025 Daz Productions Inc. All Rights Reserved.
Comments
i use a 970 to drive 3 2560x1440 monitors
I cannot figure out how to get my Vega graphics to drive my second monitor on my Ryzen 3
there does not appear to be an option on the BIOS starting up either like I did on my old PC
no signal plugging it into any motherboard outputs the old pin type or HDMI
other softwares see it like Blender Eevee and Benchmaking softwares
Looked on Toms Hardware etc some seem to think it's not possible
Usually, you use the same graphics card to run both monitors. When trying to run two monitors with two different graphics cards, this can be hit or miss, and as you noted, there may be issues when mixing brands.
In my case, ONLY my Ryzen integrated graphics are running my monitor. I do have a displayport as well as a HDMI port, but I don't have 2 HDMI ports on my motherboard, plus my 4K TV doesn't play nice with my Asrock/Ryzen graphics, so I haven't tried running two monitors, or in my case, monitor + 4K TV. I'm good with just the 4K monitor I'm using.
As to how I 'got this to work', I didn't do anything special. I didn't add the 1080Ti to the system until after I had the system up and running using the integrated graphics, and the 1080 Ti isn't connected to any monitors, just the Vega graphics via the inegrated motherboard HDMI. I plugged in the 1080 Ti into my PCIe16 slot, installed the drivers, and Daz knew just where to find the 1080 Ti...
There are some displayport to dual HDMI adaptors out there, but I've never used one of those so no idea how well they work, etc.
after breaking two PCIe slots on my old computer I refuse to touch my hardware in my box now
I would plug both into the Vega outputs if I could, just temporarily use the card output for driver updates and shadowplay
on the previous PC with the intel graphics (that is all it has now) I ran one off each fine after setting it up in the BIOS because I needed one on the 980ti for iClone, also you cannot use shadowplay without it.
(iClone still runs fine on that PC as it does not need a Nvidia card so it would on this one too but if I want to use the 980ti I would just plug a monitor into it and drag iClone's viewport window on to it.)
but
this one simply gives no signal even if it's the only monitor, as I said don't want to unseat my card
Hmmm...
I'm guessing that the Nvidia card is in the first PCIe slot? May or may not be relevant.
I suppose you could disable the Nvidia card via the control panel, with your second monitor connected to the Vega card to see if that might 'wake up' the Vega card, but this seems risky, i.e. not being able to see what's going on if the system can't find the Vega card.
Sooo, I'd suggest this thread as a starting point, to see if it makes any sense to you. Hopefully you have a different system to browse the internet with while you are poking away in the BIOS of the first one to see if you can find the settings being discussed in the OP:
https://forums.anandtech.com/threads/anyone-running-amd-and-nvidia-cards-in-the-same-system-solved.2504401/
weird thing is it obviously sees it in some software
just won't output a signal
yeah I am a bit wary about what I want to try too even though I have two computers and an iPad
(3 if I count the ancient laptop I don't use)
...I have a 2 GB 560Ti powering the displays and the Titan-X reserved just for rendering. Also still running W7 Pro so I pretty much get the full 12 GB from the Titan.
I also believe that the RTX Titan allows you to bypass WDDM as well. 1,500$ less than the Quadro 6000 and also 24 GB of VRAM.
Question. If you attach the second monitor to the 2nd GPU, does the second monitor show up in Device Manager at least?
Also, do both monitors have the same or different 'default' refresh rates? That has been known to mess with things if they are different...
could try that later
right now staring at my frozen DAZ studio scene, third attempt after crashing two
Imo the biggest factor is whether your mobo will allow it. The cheaper ones simply wont.
Edit: may be less common/relevent these days to have a problem, new post below.
Can you give a spec list, namely what is the motherboard and CPU? There should be info on that board. It could be the motherboard is not capable of doing this. But it usually is not a good idea to mix AMD and Nvidia GPUs. It is certainly possible, but not advisable. There are just so many things that can go wrong.
I do sometimes fear pushing that tab to get a GPU out. It can be hard to get to sometimes in a tight case. The big heatsink on my CPU is kind of close to where the pci tab is.
Yes, if you use a second card to drive the monitor, it will free up some memory for the 2080ti. I have two 1080tis, and the one connected to the monitor can use up to 1 GB more VRAM at times. I have had scenes that report over 10.5 GB VRAM used on that card, while the other card sits just shy of 10 GB. I have managed to get both cards over 10 GB a couple of times, I'm not sure how they both stayed rendering, I was sure the 1st card would go over.
There are two concerns. One is the 570 lacks VRAM, so in general use it could slow down if it needs to swap data. But that depends on what you are doing. However, the VRAM is actually NOT the main concern...
The real concern is that the 570 is based on Fermi, and Iray does not support Fermi anymore. You cannot render on Fermi even it had enough VRAM. I do not know if Daz ended Fermi support completely, or if it was only for the Iray plugin. Fermi might work to drive the viewport, but since the viewport has an Iray option, it is possible that Fermi is not available as an option at all. This may be a question for Daz staff. So if Daz does not support Fermi at all, then you may have no choice here.
A weird thing happened to me re:PC#1 (in sig. link) regarding the RTX dual 2080ti's. Daz would only see 1, and in the Nvidia panel I was only picking up one. I have no idea what upgrade (had windows turned off and only went on line for DIM) while I was online managed to upgrade considering I have windows Pro 10 and all upgrades off. My computer tech that built the two custom systems I own, was baffled. He moved the cards to other slots until the PC recognized both of them (motherboard can accomodate several more RTX 2080ti's) and after ordering and coming here to install 3 three different sli/nvlink system, none work. Each time, he called Nvidia and sent them photos, and overall they sent him three different link things but none worked. He finally resolved the problem by calling the Motherboard manufacturer because it was newer than the cards (meaning they had the specs after the RTX's specs and Nvidea RTX 2080ti's were nano seconds older nonconforming technology -meaning motherboards pre-those cards could also cause issues) The motherboard company and Nvidia together settled on two different link options (each link option is based on the size of the cards and the locations of the caards based on the motherboard.) The one that he expected to not work (the 2nd choice) worked. The motherboard company informed him that Nvidia is going to change how they release cards and work more closely with the motherboard manufacturers to decrease these types of issues on newer motherboards.
This thread inspired me to try 2gfx cards on my recentish computer. My previous machine's motherboard simply wouldnt detect 2 Nvidia cards at the windows hardware level, only crossfire AMDs.
But despite my newish AMD B450 motherboard having no mention of SLI support, it does detect two Nvidia video cards. 1070 and 1030. Some testing to be done in Daz!
Awesome! Please post some benchmarks. VRAM of render card before/after would be interesting. And also render times. Same scene with 1 GPU rendering and monitor and 2 GPUS (1 Rendering 1 Monitor) :))))