12 GPU Limit - Per license or per network?

[glimpse]

..
But when we have 4 licenses but still cannot use all of our 16 GPUs in a single render, 4 for each machine, each machine with a license, there is no logic explanation for the limitation.

agree here =).. hope OTOY will come with any solution for v3 (at least it would be time to do that..before comunity gets furious =DDD)

[muski]

I'm guessing here that if you have a large number of gpu's on one image you'll get severe bottlenecks over the network. When rendering with only 3 extra network gpu's, on large(ish) images (ie: 3k and above) the network gpu's stop processing every time they have to send/receive data from the master. And the larger the image the longer they stop. I've noticed drops of around 50% on very large images. I'm not sure why the 12 limit but I'm guessing beyond that there is little point as perf drop will be ridiculous.

I imagine that a solution will be 10GB network but these are simply not affordable for most.

[JNDesign]

really silly question

The new Titan Z is a dual chip card....

is that counted as 2 or 1?

again I did say it was silly question but clarification needed

cheers

[glimpse]

Yeah, Z is dual GPU card - Octane count that as two GPUs.