GPU-Oriented PCIe Expansion Cluster ?

[walee]

Let's say i want to to add a lot of GPU to one motherboard and use this kind of product that lets me install 4 gpus on 1 PCIe slot

http://amfeltec.com/products/gpu-oriented-cluster/



I was wondering if the performance would be the same as installing the 4 gpus directly on my motherboard ?

My motherboard is an ASUS RAMPAGE V edition 10 and i have 4 PCIe 3.0. So i was waondering if there's was a limitation on a much GPU you can plug on 1 motherboard ?

Amfeltec claims that with their cluster you can hook up, up to 16 gpus on 1 machine.

Can anyone please shed some light on how this work

Thank you.

[savage309]

We have not tested those, so we can't tell. Usually, esepcially with higher rays per pixel / ray bundle size, V-Ray GPU is not very PCIe bandwitdh demanding.

Best,
Blago.

[jironomo]

This looks really interesting. If you increased RPP and bundle size would there be a bottleneck anywhere else?

[KhyeKading]

This looks really interesting. If you increased RPP and bundle size would there be a bottleneck anywhere else?

I'd suggest looking at the benchmarks (https://benchmark.chaosgroup.com/gpu). You'll notice that systems with 8 cards is rendering 1 second faster than a system with 4. There is speculation in another thread of what is causing the lack of productivity above 4 cards. Other users have speculated it might be a bios/motherboard supporting that number of cards. I haven't heard anything from Chaos Group of what the issue would be, but those results steered me away from building anything with more than 4 cards per system.

[JezUK]

I'd suggest looking at the benchmarks (https://benchmark.chaosgroup.com/gpu). You'll notice that systems with 8 cards is rendering 1 second faster than a system with 4. There is speculation in another thread of what is causing the lack of productivity above 4 cards. Other users have speculated it might be a bios/motherboard supporting that number of cards. I haven't heard anything from Chaos Group of what the issue would be, but those results steered me away from building anything with more than 4 cards per system.

I personally believe at this stage that the Benchmark software is currently the main *suspect* !

Let's see

[savage309]

I personally believe at this stage that the Benchmark software is currently the main *suspect* !

Let's see

Thats correct

Best,
Blago.

[biochemical_animations]

Thats correct

Best,
Blago.

And that was sort of my point when discussing a non linear performance increase in the gpu render node thread

when I tested (rank 16) with 5 gpus and got 18.876, then (rank 9) with 6 gpus and got 17.768 sec, then (rank 7) with 7 gpus and got 17.518 sec, that is not linear performance

but if I'm rendering a 4k frame with heavy refractions, I am super happy to have those extra gpus because when working on the noise reduction step of the render they are all contributing to reducing render time during that step.

[biochemical_animations]

Let's say i want to to add a lot of GPU to one motherboard and use this kind of product that lets me install 4 gpus on 1 PCIe slot

http://amfeltec.com/products/gpu-oriented-cluster/



I was wondering if the performance would be the same as installing the 4 gpus directly on my motherboard ?

My motherboard is an ASUS RAMPAGE V edition 10 and i have 4 PCIe 3.0. So i was waondering if there's was a limitation on a much GPU you can plug on 1 motherboard ?

Amfeltec claims that with their cluster you can hook up, up to 16 gpus on 1 machine.

Can anyone please shed some light on how this work

Thank you.

I asked amfeltec tech at what gen and lane speed that runs at ( remember that pcie generation is a factor to consider along with lane speed...gen 3 runs faster then gen 2 at same lane speed) and I decided to go a different route.

plus I wasn't sure if they would simultaneously transfer or if it transfers to one card then transfers to card 2 etc...too many unknowns. I remember reading in a different thread the performance of that splitter was not what the builder expected for their renderer.

it still worked ok, but I felt there were better ways to build for my needs...plus I thought it was expensive.

the guys using this splitter were building 20 gpu rigs due to the renderer licensing.