VRAM reduction with 3rd Graphic Card used.

[PizmoSF]

This doesn't really rise to the level of a serious problem, and as I don't really know the source of the problem, I decided to mention it here as I used Octane Render exclusively with The DAZ Plug-in.

Recently I upgraded my graphics cards, I bought three Nvidia GTX 760 4GB cards, Gigabyte is the manufacturer. They are a big improvement and work very nicely. One issue has me scratching my head. When I choose card 1 & 2 under GPU configuration, I have access to most all the memory available on the cards, about 3.9GB. If I add the 3rd card, while speed does increase, the memory reduces about 500MB; it's sort of a random amount sometimes a little more, sometimes a little less. I know the memory available to Octane render is limited to that which is available to the card with the least memory, I just don't know if the reduction is due to the card or the system. It does seem to be the same card causes the reduction each time.

My apologies if this issue has been addressed elsewhere, but I was unable to find it when I searched.

Thank you,
PizmoSF

[rappet]

Maybe you can try swap slots to see if this third card is giving the same problem being in another pcie slot.
I do not know if this makes sense, but that is what I would do... Just to rule out.
Good luck.

[birdovous]

If the 3rd card you are adding is the one your display is connected to, then it is perfectly normal as part of the VRAM is taken by the system for showing your screen.

[t_3]

unfortunately this is just what to expect.

the card which is connected to display(s) is utilized by lots of stuff. of course the system (if you are on win 7 with aero on this alone cuts a 150mb off), and meanwhile there are lots of other applications (for example web browsers) that request some gpu resources to accelerate this and that. and of course daz studio itself which needs it for its ogl viewport(s).

the principle in octane is, that in order to render with multiple gpus the full scene needs to be uploaded to any one of them, so the card with the least amount of available vram also sets the limit for all of them.

ps: you can read on here for some more discussion about that (and a few thigns you can do against it): http://render.otoy.com/forum/viewtopic. ... hilit=vram

[PizmoSF]

OK, you guys are pretty dang awesome. You got me to thinking and experimenting, It wasn't the display so much, but which card was hosting the Nvidia PhysX engine.

Thank you, you are great. I love Octane render, I love the Daz Plug-in. Seriously, this is killer product, well worth every cent. Everyone should have one. You have me horribly spoiled.