Dual Video Card Setup

[Smalerbi]

Hello,

I was curious if anyone is using dual video cards in their workstation? I'm currently running a Quadro K5200 and I also have a perfectly good GTX 980 just sitting in the box. How can both cards be running in the same workstation without some sort of hardware and driver conflict? Also, how does the OS, or program know what card to use for what APP? If I understand this correctly, some programs like Aftereffects can take advantage of the CUDA cores in the video card, so in theory, the more the better. Of course it may not be worth it, if the dual cards can cause all kinds of issues with other apps.

Thanks

Scott.

[JezUK]

I always thought you needed to have the same gpus. I know my motherboard manual states that.

[Donald2B]

I've run multiple video cards quite often, but I've never tried mixing between the quadro line and game cards. In that situation, it's pretty easy. Make sure the video card drivers installed support both GPUs, install card and once booted, windows will see the card and automatically install the appropriate drivers since it already has them installed.

You could always try to install the card and see what happens? You will have to connect a monitor to the 980 to keep it initialized. It's not going to be like a tesla card where it can be active in a computer without a monitor for CUDA processing. (If my memory serves me correctly).

[savage309]

I have used Quadro M6000 & GTX 9600 for quite some time without any troubles.
I used the GTX for viewport, and the Quadro for RT GPU.
nVidia dropped the support for older GPUs in their recent drivers (the ones after 350.12), so I had to change the GPU set.
So I tried AMD w9100 for viewport and Titan X for RT GPU rendering.

Suprisingly to me, all worked fine - the OS (Win 7) sees all the GPUs and works without problems.
I've used CUDA only for RT GPU, however (and the w9100 for Maya/Max viewports).

[JezUK]

Can someone please confirm, does vray RT support SLI ? Or can RT only use one card ?

[savage309]

Can someone please confirm, does vray RT support SLI ? Or can RT only use one card ?

V-Ray RT can use all the GPUs the system has, but the SLI should be off (you just start vray and it will be fine by itself).
There is a tool named ocldeviceselect that comes with the V-Ray installation, which lets you to choose which GPUs from the system will be used for rendering.

[JezUK]

Thanks for your reply.

I'm building a new workstation and was able to purchase two new K4200 Quadro cards at a very good price.

I currently have two monitors but my plan is to purchase a third monitor once I have built my machine.

I anticipate monitor resolutions to be 2560, 1920 and the new third monitor also being either 1920 or 2560 as well.

Can you give me some guidance as to how best I should configure RT with such a setup ? I mean, would I just let RT use both cards, or only the one card which is driving the third monitor ? (or would it work if I put all 3 monitors onto one card and dedicate the 'free' card exclusively to RT ?). Excuse the dumb question, I'm trying to understand this technology before my cards arrive.

Many thanks

[savage309]

I think you will have to put all the monitors on one of the GPUs, since there is no way to have monitors on different GPUs on any OS as far as I am concerned.
So you have two options. If you use both of the GPUs for rendering, the rendering will be faster, but the UI of the OS may become sluggish (since the GPU with the monitors will be busy with the rendering) or you can render only using one of the GPUs (make sure that you are using the one that does not has monitors attach). In the second use case, the rendering will be slower, but the UI will be okay.
You can do something in between - V-Ray allows you to set "bundle size" and "rays per pixel" - this is basically the size of the tasks V-Ray gives to those GPUs. You can try with low settings there (32 or 64 bundle size and 1 ray per pixel) and both GPUs used for rendering - there is a chance that the render speed might be better than using one GPU and the UI might be okay (but you have to test to see what works best for you).

[JezUK]

I think you will have to put all the monitors on one of the GPUs, since there is no way to have monitors on different GPUs on any OS as far as I am concerned.
So you have two options. If you use both of the GPUs for rendering, the rendering will be faster, but the UI of the OS may become sluggish (since the GPU with the monitors will be busy with the rendering) or you can render only using one of the GPUs (make sure that you are using the one that does not has monitors attach). In the second use case, the rendering will be slower, but the UI will be okay.
You can do something in between - V-Ray allows you to set "bundle size" and "rays per pixel" - this is basically the size of the tasks V-Ray gives to those GPUs. You can try with low settings there (32 or 64 bundle size and 1 ray per pixel) and both GPUs used for rendering - there is a chance that the render speed might be better than using one GPU and the UI might be okay (but you have to test to see what works best for you).

Thank you so much for your guidance - I've done exactly as you said and 3DS Max with 2 x K4200 (one for monitors and the 2nd just for RT) works fantastically. I'm not used to this kind of performance, but the differences this is going to make to my productivity is going to be awesome

Thanks once again

[eyepiz]

I have used Quadro M6000 & GTX 9600 for quite some time without any troubles.
I used the GTX for viewport, and the Quadro for RT GPU.
nVidia dropped the support for older GPUs in their recent drivers (the ones after 350.12), so I had to change the GPU set.
So I tried AMD w9100 for viewport and Titan X for RT GPU rendering.

Suprisingly to me, all worked fine - the OS (Win 7) sees all the GPUs and works without problems.
I've used CUDA only for RT GPU, however (and the w9100 for Maya/Max viewports).

Hi Blagovest,

I'm currently running Titan's in my system but I'm thinking about picking up a K6000 for the Viewport I have some huge archviz scene that just crawl with the Titans. Could I run the viewport with the k6000 and use the Titans for RT. Would this set up work? do I need any special configuration for the drivers?

I would really appreciate any suggestions.

Thank you!

[savage309]

Just connect the monitor to the k6000, use ocldeviceselect to exclude that GPU from RT rendering, install latest nVidia driver + V-Ray 3.20.02 (or any V-Ray version and driver 350.12) and you will be fine.

[eyepiz]

Just connect the monitor to the k6000, use ocldeviceselect to exclude that GPU from RT rendering, install latest nVidia driver + V-Ray 3.20.02 (or any V-Ray version and driver 350.12) and you will be fine.

Thanks! I assume I need to have both GTX and Quadro Drivers installed?

[savage309]

This question is more for nVidia guys, but according to what I see (and mine experience) - if you check the supported GPUs with the Quadro Driver http://www.nvidia.com/download/drive...px/86066/en-us you can see that there are the Titans as well, so you should install only that one. I've always done that and it so far works great.

[eyepiz]

This question is more for nVidia guys, but according to what I see (and mine experience) - if you check the supported GPUs with the Quadro Driver http://www.nvidia.com/download/drive...px/86066/en-us you can see that there are the Titans as well, so you should install only that one. I've always done that and it so far works great.

LINUX X64 (AMD64/EM64T) DISPLAY DRIVER? I'm ruining windows 7 Pro

[savage309]

Sorry, I've pasted wrong link.
It is updated now.