Rtx 2080 and gtx 1080

Hi there.
Want to know whether there is any benefit in having two different Nvidia cards on the same PC, for blender.
I have recently upgraded from GTX 1080 to RTX 2080 super.
Currently I have no PCI slot to have two cards at once on my motherboard, but I will likely build myself a new computer soon’ish. Thinking on whether I should care whether it has two slots for GPU :slight_smile:

So… Considering how different these two cards are, one being CUDA, the other doing the Nvdia Raytracing acceleration thing, can I run them both at once and render faster, than just rending with the RTX?

Im not sure but I think you can either render a frame with CUDA or OptiX,
You could use both cards to render with CUDA, but you won’t get the RTX speed up this way

…unless you will be able to run 2 instances of blender at once and render frames simultaneously. That won’t work for still images thou

Their is a system variable now to use OptiX on GTX cards CYCLES_OPTIX_TEST. Otherwise, using the right program, it’s possible to render with both very fast.

Didn’t really understand what you said :slight_smile:
So… If I just have them both on one motherboard, I can render with Optix acceleration, using both? If so, really cool. Do I need to set it up in any special way for that to work, or will it just work by default? If I do, what are the steps?
Do I need an SLI connection between the two?

You need to setup your system environment with a new variable CYCLES_OPTIX_TEST set to 1. I think on Windows you can type set CYCLES_OPTIX_TEST=1 in the cmd before you launch blender. Depending on your OS, google how to best set such variable.