[alc96]

Hi everyone, I am looking for a new workstation to perform a CFD simulation with the following conditions:

- Software: Ansys Fluent
- License constraints: no
- Type of Simulation: 3D Unsteady Reynolds Average Navier-Stokes simulation, single-phase incompressible flow, simulation of the wind turbine whole rotor with the sliding mesh approach
- Cell count: I don't know exactly but I think around 5 - 10 million
- GPU: It is just for post-processing so I think that a graphics card with 8 GB will be okay
- Budget: 15.000 €

After some research, I am focalized on Dell Workstation with the following features:
- CPU: Dual Intel Xeon Gold 6248R (24 cores, 6 memory channels, from 3,00 GHz up to 4,00 GHz Turbo)
- GPU: Nvidia T1000, 8GB
- RAM: 256 GB, 8 x 32 GB DDR4

I have read that core count and memory bandwidth need to be balanced, but this is the first time that buys a computer like this so I don't want to have missed something important in the process of analysis.

So do you think that this workstation could be okay for the application above?

Thank you

[wkernkamp]

Originally Posted by alc96

Hi everyone, I am looking for a new workstation to perform a CFD simulation with the following conditions:

- Budget: 15.000 €

After some research, I am focalized on Dell Workstation with the following features:
- CPU: Dual Intel Xeon Gold 6248R (24 cores, 6 memory channels, from 3,00 GHz up to 4,00 GHz Turbo)
- GPU: Nvidia T1000, 8GB
- RAM: 256 GB, 8 x 32 GB DDR4

So do you think that this workstation could be okay for the application above?

Thank you

You have a very large budget available. So you could source a top of the line Dual AMD EPYC Genua system, which would outperform the system you selected.


See also discussion here: Workstation recommendation

[alc96]

Thank you, just to confirm: Dual AMD EPYC performs better because of the memory bandwidth right? (8 memory channels up to 3200 MHz while the Intel Processor has 6 memory channels up to 2933 MHz)

For example, the following workstation should be better (?):
- CPU: Dual AMD EPYC 7513 (32 x 2 cores, 8 x 2 memory channels up to 3200 MHz)
- RAM: 256 GB, populated as 16 x 16 GB DDR4, 3200 MHz

[wkernkamp]

Originally Posted by alc96

Thank you, just to confirm: Dual AMD EPYC performs better because of the memory bandwidth right? (8 memory channels up to 3200 MHz while the Intel Processor has 6 memory channels up to 2933 MHz)

For example, the following workstation should be better (?):
- CPU: Dual AMD EPYC 7513 (32 x 2 cores, 8 x 2 memory channels up to 3200 MHz)
- RAM: 256 GB, populated as 16 x 16 GB DDR4, 3200 MHz

You are correct, but I think the best CPU is the 7773X. flotus, please confirm.

[flotus1]

Correct, Milan-X had some pretty nice price cuts since Genoa was released. For obvious reasons, Genoa is just better. But you probably won't find anyone offering a workstation with 2x Epyc Genoa right now. And you won't find the parts you need to build it yourself. Last nor least, 15000€ might actually not be enough for parts to outperform dual-socket 7573X. Everything about Genoa is expensive.

So for now, Milan-X is still your best bet for workstations.
the 64-core 7773X retails for around 6000€ these days. Probably still too expensive for a 15000€ workstation.
So the 32-core 7573X seems like the best choice right now. Don't let your SI rip you off. These CPUs were ~6000$ at release, but now start at 3700€ retail.

[alc96]

Thank you, just a last thing: there is any particular advice regarding hard drive devices? Does the choice of SSD or HHD have an impact on the performance of the workstation?

[flotus1]

For the operating system and stuff, you definitely want an SSD. SATA or NVMe doesn't matter whole lot.
Fast SSDs can speed up the solver if you do lots of writes while the simulation is running. E.g. periodically saving transient results.
And an SSD will speed up tasks encountered in pre- and post-processing. Like loading the simulation results into your post-processing software.

Long story short: In this price range (or really any price range above low-budget), get at least a 2TB m.2 NVMe SSD for the operating system, programs, and your current simulation projects. These things cost less than 200€ these days.
How you do storage beyond that depends on use-case. With your sliding mesh URANS simulations, chances are you actually benefit from more fast storage.