Recommended CPU for simulations?

Hi I’m new to this forum.

I’m currently going to get a new PC. I was wondering, what is a good budget CPU for calculating/baking simulations quickly in Blender, let it be rigid body, fluid or cloth. My current CPU that I’m planning to buy is Ryzen 5 3600. Is it good enough for simulations?

Also, could you also recommend some specs for a good CPU for simulations?

Thanks

The answer to this question also interests me too. Anyone have a good simulation scene that could share to do testing?

That depends entirely on the resolution and size of the simulation.
The bigger the simulation + the higher the resolution the more calculations your computer has to do.

The thing with simulations is that most computers aren’t fast enough - the moment you have more performance available the more likely it is that you increase the resolution in order to get more quality.
And you need a high resolution for quality - especially for fluid/smoke. Rigid body simulations and cloth are often trivial in terms of performance demand, fluid/smoke on the other hand can easily overpower the strongest commercially available CPU (depending on your demands for quality or complexity).
That being said, I absolutely wouldn’t recommend an Ryzen 5 for 3D in the year 2021 especially not for doing simulations.
The question for you is, how much complexity/quality do you really need and how often do you need it?
How much of it is fluids/smoke because this is the most demanding discipline of all simulations.
Are you just dabbling with it as a hobby, or do you want to do it in any professional capacity?
If its the former, invest at least a 150 bucks more and get an Ryzen 7 with 8 cores (or more), if its the latter I would recommend to put some money on the side and purchase the strongest CPU you can afford with the most amount of cores and also don’t forget the RAM, you’ll needs lots of it for fluids/smoke.
Blender itself is also problematic as it is pretty bad in terms of performance (fluids/smoke, the rest is ok).
If you want to do it professionally, I’d suggest you learn Houdini as it is much more performant as well as competent. Yes, it costs money and time to learn but it will pay off in the long run.

The rule of thumb for simulations is: the more the better - too little and your results will suffer or you fail completely.

One of the questions is how much the diverse simulations (rigid bodies, soft bodies, cloth, particles etc) are multicore and scalable by them.

Ok thks. I’ll go for the Ryzen 7, 8 cores that you recommended, cause I’m just doing it as a hobby.

One question, which Ryzen 7 CPU should I go for? There are like 11 types. What is the most budget but good Ryzen 7 type?

Within your available budget you choose something with good single thread performance and then the higher the number of threads the better. The following is a benchmark for single threaded performance. Then you from the left arrow icon in each item you can see the number of threads of each CPU:

I believe the new M1x Mac Mini (coming in next few months) would be a good option as the M1 has shown great promise. Not sure how you feel about Macs though! I abandoned them a decade ago but these new chips have drawn me back in. Theres a whole thread here: https://blenderartists.org/t/mac-m1-and-blender

In theory all modern available CPU’s are able to compute fluid simulation. Caveat is some fluid sims need A LOT of computing power to be done in reasonable time.

Question is what kind of simulation are you into? If you want to go big, you will need big budget. Second thing that was already mentioned is proper simulation resolution and other optimisations which you want to do regardless of the CPU you have.
If you start playing with Mantaflow you will inevidably hit a wall at some point where the sim is too big for your hardware. That is the nature of the physic sims.

My advice is - go as big as your budget can handle.

As for Mac’s - I wouldn’t because of the uncertain future of GPU rendering on them, but that is another topic.

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