How to configure another gpu for display only?

Raymand

Well, after a 3 month wait, I finally won the Nvidia lottery. That is, I kept adding my email to the "Notify Me" list when their Founder's edition 1080ti's were in stock. They seem to be getting shipments every few weeks, and usually by the time I got the email, they were gone in seconds. This time they sent an email the day before saying they would be in stock, and I used a browser add-in to refresh my browser every 15 seconds, and I snagged two. Even then, it wasn't easy. Their site was slammed when they put them up. Damn bitcoin miners!

So, I'll have two in a couple weeks, and I wondered about the best way to set them up. In particular, I understand Microsoft grabs a ton of memory if one is used for display, and it might be better to add a more pedestrian gpu to drive the display. I have a few technical questions:

Is there a way to tell Daz Studio, or the Iray rendering engine, that this 3rd graphic card is not to be used for rendering? This seems important because I understand you are limited to the memory size of the smallest card in the pool. Or is it necessary to choose a non-Nvidia card like a Radeon so Iray does not even consider using it in the rendering pool?

Second, for a pc running Daz Studio, with the 1080ti's dedicated to rendering, what is a sufficient card to handle just the display work? Is a 1050 or 1060 good enough? (Presuming I can configure it so Iray does not try to render on it.) Or what's a comparable Radeon card that is sufficient?

Third, like all high-end graphic cards, the 1080ti's can use 16 pci express lanes each, but unless I get a Threadripper or the highest-end Intel CPU, there won't be enough lanes on the motherboard to give 16 to each. Will it be a big bottleneck to run one of them with 4 or 8 lanes?

Finally, I think I saw that there is no advantage to use the SLI bridge connector between the 2 1080ti's in this setup. Is this right?

Thanks for your advice.

 

namffuak

Answering the questions in no particular order -

1) You don't tell Studio or Iray to not use a particular card - it works the other way. Studio will list the available supported devices and you select which ones you want to use.

2) Iray does not use SLI and may actually have problems if it is enabled.

3) Iray will use all cards you tell it to providing there is enough memory on the card - assuming a 2 GB, 4 GB, an 8 GB set of cards, a 1.8 GB scene will use all three. A 2.2 GB scene will cause the 2 GB card to be dropped at render initialization. A 4.1 GB scene will cause both the 2 and 4 GB cards to get dropped at initialization. And a 9 GB scene will cause all three cards to drop out and automatically switch to the CPU for rendering, even if you haven't explicitly included the cpu in the set of resources to use.

4) PCI lanes really only count at startup, when the resources are written to the cards; if the actual render runs over two to three minutes the PCI lane count will have a negligible effect on the over-all time.

5) I have a GT 740 running two 27-inch 1080p monitors with a 980 TI and a 1080 TI doing the rendering; virtually any card that has enough memory and video ports for the monitor(s) you want to use will work.

Raymand

That's excellent news. I'll just tell it to use the 1080ti's to render and I'll be all set. And thank you for the advice on the other topics.

I may have to get a 980 for display purposes. Nvidia sells from 1060's all the way up to Titans directly, and when they come in, they all sell out in minutes, even the 1060's. The bitminers are like a zombie apocalypse.

Thank you for your help.

fastbike1

The card that runs the display is the card that's plugged into the monitor(s). You don't have to configure the gpu for display beyond connecting to the monitors. Simple as that.