Threadripper or mainstream CPU with multiple GPU’s ?

[Joelaff]

FWIW, on the 7995wx we have a Asetek 836S-M1A 360mm Threadripper CPU Cooler.

[haniel1107]

FWIW, on the 7995wx we have a Asetek 836S-M1A 360mm Threadripper CPU Cooler.

Joelaff, also very good to know... thanks

[haniel1107]

Joelaff I think I would go for the asetek watercooler.. had good experience with the 3990x

[Joelaff]

We had the Noctua on the 5975wx. It also worked well. On render nodes we use the BeQuiet rack mount models since they fit in 4U cases.

[Muhammed_Hamed]

V-ray GPU rendering becoming more advanced but still missing CPU functionalities – will this change to a complete similarity over time?

Hi CTRL SPACE

Our long-term roadmap include Toon Shading on GPU and displacement optimizations, the recent V-Ray 7 added support for Caustics on GPU
If there is a feature you would like to see on GPU, please reach out to us. We don't add every single node/procedural texture to V-Ray GPU, usually we focus on the features people ask for. For V-Ray 7 we are putting a lot of effort into optimizing the performance.

Project file size with large amounts of objects and materials, Forest Pack for major landscaping etc. – Performance on Threadripper CPU and its large amount of ram vs multi GPU on mainstream CPU (with a possible video ram bottleneck?).

The issue with big exterior projects was usually time-to-first-pixel on GPU, this is improved now in V-Ray 7
Running into the GPU memory limitations is less of a concern nowadays with Out Of Core Textures, which doesn't affect GPU performance. You can store all of your bitmaps into system memory to keep the VRAM to your instances and geometry.

Software multi thread functionality vs high single core clock speed.

Talking about 3Ds Max, single threaded performance plays a key role in many things. Threadrippers are great, but will never be as fast as recent Ryzens in single-Threaded tasks. I usually prefer Ryzens

Max possible number of large GPU’s on non-threadripper motherboard? PCI lanes and support/speed.

You can fit 2x 4090s easily with a Ryzen 9950X in a big case, and if you use riser cables(like my personal setup here) you could use up to 3x 4090s
With Threadrippers, you could setup up to 7 GPUs in the same way, using Riser Cables. Here is my Threadipper workstation with 4x 3090s, I can add up to 7 cards on the same rack
With the 9950X and 7950X, the bandwidth is pretty good. You don't lose any performance, it the better choice if you want 2 or 3 cards per machine

Cost of adding/upgrading GPU’s along the way vs CPU/motherboard.

swapping a GPU vs buying a new system, this one is a big advantage of GPU rendering.

So TLDR: Where does the Threadripper shine vs a mainstream CPU with multi GPU’s today or in 5 years time, - according to Chaos Group maybe?

Depends on the use case, the GPU workflow might not be suitable for everyone's needs
For people that use 256 or 512 GB of system memory on big exterior/VFX projects, this is a no no for GPU rendering.
On the other hand there is Bugatti and Porsche, all of their high resolution rendering and technical animations are being done with V-Ray GPU. Some smaller studios in VFX has been on GPU rendering, the bigger the team/the project the harder it will be to move to GPU
For building a machine, you don't necessarily need to set it up in one direction, get a 9950X + one 4090 and see if CPU or GPU works better for your projects.
The 9950X is a great value CPU at this point of time for the performance you get.

Best,
Muhammed

[Muhammed_Hamed]

General question regarding GPU rendering: as I understand, the use of double the amount of GPU's of the same make see an almost double performance as long as your project fits into the ram of one of them..?

Yes, V-Ray GPU scales near linearly with performance. If you add a second GPU, you get nearly 2x the performance
Here is some data I published a while back,

https://support.chaos.com/hc/en-us/a...-and-RTX-modes

[haniel1107]

Hello Muhammed_Hamed, may I ask, what do you think about the AMD Ryzen Threadripper 7980X 64-Cores.
I think about to switch from 3990x to this one. I prefer CPU rendering and hoping interactive and rendering will be some faster. I would take over my RTX 4090 and plan to install 126GB Ram.

[Muhammed_Hamed]

Hello Muhammed_Hamed, may I ask, what do you think about the AMD Ryzen Threadripper 7980X 64-Cores.
I think about to switch from 3990x to this one. I prefer CPU rendering and hoping interactive and rendering will be some faster. I would take over my RTX 4090 and plan to install 126GB Ram.

Both are 64-Cores, I think you will see a difference because of the architecture improvements. I see around 40% speedup at most, it is not bad

[Joelaff]

Not to mention much better single threaded with the newer generations as well, esp with PBO enabled for additional boost clock. But, as I mentioned above a 32 core Threadripper would not be a good choice. The 9950x would likely be as fast or faster for most tasks other than pure rendering on jobs that multi-thread well. If you go Threadripper do 64 core minimum.

[haniel1107]

Both are 64-Cores, I think you will see a difference because of the architecture improvements. I see around 40% speedup at most, it is not bad

Hi Muhammed_Hamed just like to report, today I have installed my 7980x and made a Vray Benchmark, it says 125.603 which is double than my 3990x with 60.000. Of course no OC, because I don't know what I would need to do...
Summary: very happy with this first result.. regarding 3990x I now from the past, you had a much higher score, right?

Thanks again for tips, here and there