Dual GPUs on current Mac Pros

[Jeremy Garchow]

Moi? Bicker?

[Walter Soyka]

[Christian Schumacher] “But what about AVID or Smoke? Or any post production related software for that matter? Like AE, Motion, C4D, Lightworks, Edius,etc…Shouldn’t all of them go dual GPU friendly?”

Ae is multiple-GPU friendly, with these significant caveats: they are only used for the 3D ray-tracing renderer, and they must be CUDA-enabled NVIDIA cards. (The Ae ray-tracer was built on top of the NVIDIA OptiX library.)

Smoke renders on OpenGL, and I think OpenGL assumes a single GPU. NVIDIA has SLI and AMD has CrossFireX, both of which are mechanisms for allowing each GPU to process different portions of the same scene. With multiple GPUs, it may be possible to run an independent OpenGL context on each, allowing each GPU to render one whole frame at a time and compiling the results. Personally, I’d prefer to see Smoke eventually transition away from an OpenGL renderer to a purely computational renderer, but that’s a separate conversation.

C4D has an OpenGL-accelerated viewport (see OpenGL multiple GPU notes above), and a purely CPU-driven final renderer. OpenGL would not be appropriate at all for final renders. There’s a lot of work going on around GPU-accelerated rendering industry-wide, but Octane, the only commercially-available GPU renderer for C4D relies on CUDA. OpenCL support is planned for the indefinite future. Octane’s Mac support came well after Windows support, so I’m not sure that the new Mac Pro is going to provide a big impetus for OpenCL support. At least for the time being, CPU-based rendering is still the standard.

Looking at the software you mention in general, there are big opportunities for multiple GPU support on compute tasks, but that will require implementing renderers with OpenCL and will take time.

Walter Soyka
Principal & Designer at Keen Live
Motion Graphics, Widescreen Events, Presentation Design, and Consulting
RenderBreak Blog – What I’m thinking when my workstation’s thinking
Creative Cow Forum Host: Live & Stage Events

[Christian Schumacher]

Thanks for the amazing summary, Walter.