New PC for Blender - GPU or CPU?

Hi everyone!

We are using Blender more and more on a semi-professional level for marketing purposes in our company.
I suggested to buy a dedicated single PC to perform the rendering instead of using my work-PC.
But I am not sure, whether it is better to buy a PC with a strong CPU or GPU to do the rendering.
I cannot find benchmarks comparing both. There are CPU-benchmarks with the Laundromat-Scene, but this is not setup for GPU-rendering, so that a comparison is not possible.

Assuming, we want to spend 1000 € for either a CPU or GPU, which is the better choice?

Also, I find that Blender crashes more often, when I use GPU compute. I assume this is related to the memory consumption of some scenes. Can someone confirm, that the memory on the graphics card is used for GPU rendering, while PC-RAM is used for CPU rendering? That would mean, a CPU is the safer choice, since is it a lot easier to buy 32 or 64 GB or RAM than a graphics card with this amount of memory, right?
My Blender crashes when running out of memory…

Looking forward to your comments! Thanks a lot!

Michael

It depends on the size and complexity of your Scenes.

Correct. That means, if your Scenes are incredibly complex and take up more gigs RAM than a few (or VRAM, the GPU memory), then you should consider using a CPU, since like you already said, you can buy pretty much as much RAM as you want (and just stack it), but it’s hard to get graphics Cards with more than like 11 gigs VRAM.

EDIT: I suggest you to look at the AMD Threadripper CPUs. No Promotion here, but they give quite nice multithreading Performance for the Price.

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Hey there,
I would recommend to wait till amd Zen 2 series is released. It looks really promising and in case it is true then it is gonna be quite something. Regarding 1000 € budget range it could be threadripper 3950x and oh sweet 48 cores/96 threads and that is MASSIVE. Now I am not 100% sure if Blender (cycles) can handle(benefit of off) that many cores/threads but it is still worth to consider it.

Plus a litle bit of prophecy here : https://www.youtube.com/watch?v=PCdsTBsH-rI

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Thanks to both of you for your prompt reply! That helps.

If you’re using 2.79b or earlier, try either a daily-build of 2.79 or 2.80 from https://builder.blender.org/download/ as I believe Cycles support for out-of-core GPU memory management was released after the official 2.79b version.

Cycles can now render things that won’t fit in GPU memory at something like a 30% performance penalty typically. Of course there’s a limit to this, and in some cases the performance may be so bad that it’s not worth it.

You’ll also get support for GPU+CPU rendering in newer versions.

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GPU can use system memory too, but you loose a lot in performance if it’s too much. For big scenes, CPU is the way to go and with AMD bringing so much threads in consumer CPUs, it’s a real chance.
Here you can compare CPUs and GPUs, you can choose what you want to compare even https://download.blender.org/institute/benchmark/latest_snapshot.html

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Thx, I am using 2.79b and will try a later version to see, if that solves my memory-crash-issues.

By the way, it is quite easy to get to a point where you need a lot of memory, if you are working with FLIP FLUID animations :slight_smile:

Also thx for the comparison table! And true, I heard about CPU+GPU coming up. Maybe that is the best solution. This is coming with 2.80, right? I guess it is still a few month before we see the final release. I hate waiting :slight_smile:

I wouldn’t cheap out on either one too much. A gigantic GPU will be hindered by an underpowered CPU, but you would be loosing a lot of potential performance if you skimp on the GPU (especially if you use EEVEE).

GPU+CPU is in the current 2.79 nightly builds. The current builds of 2.79 and 2.80 generally always contain the same version of Cycles with the same new features (20x0 Nvidia support, GPU+CPU, etc.)

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Just tried and it works :slight_smile: Thanks!

Hi, I’ve tried the latest 2.79 experimental build for win 64 and it’s not identifying my GPU. Even thought 2.79b standard recognizes it and cuda-z recognises the GPU as capabale of 2.1 computing. Any tips on getting this to work?

I have dual system that has intel and gt-550M nvidia on win 10 64bit and have already invoked the option to ‘run with nvidia processor’. However, this doesn’t enable the gpu+cpu functionality and ghosts out ‘GPU’ under the render toolbar.

Thanks,
Ian

blender-2.79.0-git.111179beb0b1-windows64

I believe Cycles now requires compute capability 3.0 or higher, so your eight year old video card is no longer supported in the current version of Cycles. Should still work fine in 2.79b of course.

From: https://docs.blender.org/manual/en/dev/render/cycles/gpu_rendering.html

“Nvidia CUDA is supported for GPU rendering with Nvidia graphics cards. We support graphics cards starting from GTX 6xx (computing capability from 3.0 to 6.1).”

(actually the 6.1 upper limit is out of date as the 7.x compute capability of the 20x0 cards is now supported as well)

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