spliting usage of graphics card?

Mon Dec 24, 2012 12:53 am

Hi guys was just wondering if it would be possible to set up a cpu with 3 graphics card where I can dedicate 2 gpus towards Octane render and the other card for the rest of the cpu. Usually the whole cpu lags up once I run octane, so I wanted to somehow split the usage of the gpus. I know it is written in the manual, but how would i go about setting it up. Do i need to connect all 3 gpus to a sli bridge? (2 gtx680's and 1 gtx660ti) or just the 2 gtx680's. Just wanted to make sure before getting an extra card. Any help would be great! thanks

Mon Dec 24, 2012 3:24 am

Hi franchais,

Octane doesn't use SLI so no bridge or anything is required for octane.
Just plug your monitor into the one you want to use for display, and then go to file->preferences->Cuda Devices, and untick the one used for display.
You might want to check your motherboard, as some of these come with an integrated video card which will do ok for displaying octane (perhaps not so much for 3d applications).

Thanks
Chris.

Mon Dec 24, 2012 5:16 am

I had a similar question, but in the form of a request.

I only have two GPUs, so dedicating half of my processing power isn't really something I'm going to do. I would like something like a percentage of the card I could dedicate to octane, and leave the rest to my OS. Just a simple slider like some Adobe products have where I could chose between like 20% and 100% (maybe total or per GPU)

Mon Dec 24, 2012 3:25 pm

i use ati + nvidia together. without any lags. i'll advice to you to do like me

Tue Dec 25, 2012 3:27 am

Thanks for the info guys! So all this while I've have been using SLI, would it hinder the performance of octane or it doesn't really matter.

Wed Dec 26, 2012 4:37 pm

Yes - I want to know this as well... I have two 460s and do not currently have them in same machine. I was going to install 2nd into workstation in the next day or two.

If using just two cards in SLI, will Octane see two cards or are they seen as one? (with no ability to choose one or the other for rendering?)

I do not need to do SLI, but since I do play the occasional game, it would be nice.. in other words, if I can use SLI when playing - but SLI is completely ignored by Octane and it just sees them as two cards, as if SLI was not enabled, this would rock.

Wed Dec 26, 2012 9:47 pm

Yes, regardless of whether you have SLI enabled octane will see each GPU as a separate one in the cuda devices list.
This includes seeing both GPU's of a 590 or 690.

It is recommended to turn SLI off, however if you do tests and don't find any problems with it on, then just go ahead and leave it on so you don't have to switch it on/off for gaming.

Thanks
Chris.