Choosing which GPU is used as Primary Card for rendering

swordkensia

Hi Folks,

I am about to invest in a 1080ti, which I shall be paring with my existing 1070..,

My question is, is it possible to tell Iray to use the 1080ti as my primary rendering card, and the 1070, which will also be driving the display, to be my seconday card.??

The reason I ask is, Its my understanding that Iray only utilises about 60-70% of the rendering power of a 2nd card (born out in my own tests with my dual 1070's), so if I remove an existsing 1070, I stand to loose alot of the rendering power of the 1080ti.., unless I guess I use the 1080ti to power the display., but then Iray still reduces the rendering capability of that card also, In order to have some juice for the display interface.., etc.

I know that octane render allows you to designate the primary and secondary cards, So I am hoping that there maybe a similar setting somewhere for Iray.

If any Iray Gurus out there could advise that would be grand.

Cheers,

S.K.

 

 

Tobor

Since you are free to experiment I think that's the best approach. Try what works for you. The Pascal-based cards are a new breed, so any experience with the prior generation(s) may not apply.

I believe there's no software control for setting the primary or secondary cards used for render -- e.g. Device 0 and Device 1 -- and this comes from the PCI-e slots the cards are plugged in to. This may vary between motherboards, so it's best to try it for yourself. I had to find the right combination on my Dell.

Do remember that your 1080ti will need both a 6- and 8-pin external power connection, whereas your 1070s use only the single 6-pin. Hopefully you've got an extra Molex on your PS for it. My PS can handle the watts for a 1080ti, but has no free circuit branches available.

swordkensia

Thanks Tobor,

Aha, thats a thought......., . Like you say I shall have to experiment, all part of the fun I guess :)

On power I'm good, running a 1000Watt modular PSU.

Cheers,

S.K.