[Slash]

I found a very good offer for 128 gb (4x32) samsung 2666 MHz, do you think that can I istall it instead of the 3200MHz?

[flotus1]

You could do that, but I would strongly advise against it. I am using 16x32GB Samsung DDR4-2666 reg ECC, since they only cost 100€ per DIMM and I have first gen Epyc CPUs.
One of the defining features of Epyc CPUs for engineering workloads is its 8 memory channels. Using only 4 DIMMs, you throw away half of the potential performance. Using memory slower than DDR4-3200 nets you another step-down in performance.
For each Epyc CPU, you need 8 identical DIMMs. The optimal configuration for one Epyc Rome CPU is 8x DDR4-3200 dual-rank.
Since I can already hear you typing: dual-rank is slightly faster than single-rank thanks to rank interleaving.

[Slash]

Ok thanks, in this moment I will buy only one Epyc 7352 and 4x32 gb of ram. When I'll buy the second Epyc, then I'll also buy the other 4x32 gb of ram. It is only a money issue.

[flotus1]

Mate...8 DIMMS per CPU.
1 CPU: 8 DIMMs
2 CPUs: 16 DIMMs

[Slash]

I'm thinking about buying a more powerful single socket configuration instead of a dual socket (one single epyc 7352 with the possibility to expand to dual). This is because the supermicro motherboard h11dsi rev2 is very hard to find and the delivery times are very long. First question: do you suggest this way? (with an asus or gigabyte motherboard) Second question: I'm thinking about a single Epyc 7452 or a 7502p, which of these do you suggest?

[flotus1]

Which country do you live in? Sourcing a Supermicro H11DSi rev. 2 should be feasible.

So let me see if I understood you correctly: You want to buy a single-socket board now, and then later upgrade to dual-socket? I don't think that is the best course of action. You will have to sell your board at a significant loss. And in case you bought a single-socket Epyc CPU (P suffix), you will also have to sell that with even higher loss. Judging by the first generation of Epyc, their value drops immensely once taken out of the box.
And in terms of CFD performance, the benefit of a 32-core Epyc compared to one with 24 cores is pretty small. Memory bandwidth limitations strike again.

[Slash]

No I did not explain myself very well. The options are: 1) Dual socket supermicro motherboard with only one Epyc 7352 (24core) and in the future I'll buy the second cpu. 2) Single socket Gygabyte motherboard with Epyc 7452 (32core).

[flotus1]

I see, so I misunderstood your thought process.
But still, the 24-core will get you to nearly 90% of the performance of a 32-core in parallel CFD. A single CPU with higher core count is not nearly as fast as two CPUs.

[Slash]

Ok, so the best solution for you is the dual socket cpu with only one Epyc at this moment. What is the ram configuration that you suggest (8 x cpus dimms available)? My largest work occupies about 200 Gb but it doesn't happen very offen to work with such large job. Take into account that in the future I'll install the second cpu and the related ram dimms.

[Habib-CFD]

Originally Posted by Slash

No I did not explain myself very well. The options are: 1) Dual socket supermicro motherboard with only one Epyc 7352 (24core) and in the future I'll buy the second cpu. 2) Single socket Gygabyte motherboard with Epyc 7452 (32core).

Hi, be careful about the multi core license. The license price of e.g Abaqus depends on the cores number. Ryzen 3900X is the best option up to 6 core license. For a limited budget the 2950X or even 2920x still give you very high performance with usual and cheaper 3200MHz RAM. You can not find any 8G 3200MHz ECC registered memory. Two Epyc processor needs 16*16GB 3200MHz ECC registered memory!!! The Epyc Rome series are really cool and solid hardware but I do not recommend with limited budget.

[Slash]

The licence is not a problem in this moment because one of my client rents a licence for me.

[flotus1]

Originally Posted by Slash

Ok, so the best solution for you is the dual socket cpu with only one Epyc at this moment. What is the ram configuration that you suggest (8 x cpus dimms available)? My largest work occupies about 200 Gb but it doesn't happen very offen to work with such large job. Take into account that in the future I'll install the second cpu and the related ram dimms.

Not sure what you want to hear. If your largest jobs require 200GB, you will have to install 256GB of RAM. With only one CPU to start with, that means 8x32GB.

[Slash]

Thanks, I bought the workstation. One Amd Epyc 7352, motherboard h11dsi, 8x32gb Kingstone Ecc 3200 MHz, graphic card nvidia rtx 4000, nvme samsung evo plus 1tb. I'm excited to assemble these components.

[Tempest]

What's the total cost and how is the performance?

[Slash]

The total cost assembled by me is near 5000 euro, for the performance I don't know because I'm still waiting the Supermicro motherboard from USA.

[crestang]

Originally Posted by Slash

Hello, I'm a mechanical engineer. I'm thinking about buying a new workstation/server to do FEM structural simulations (abaqus, ansys, nastran etc). My question is: is it better to buy a two socket Intel Xeon scalable Silver 4216 or 4214 or a single AMD Ryzen threadripper 3960X?

The thing is that the xeon processors are well known in server industry and the AMD proposal in that field is the Epyc one and not Ryzen. But at a price of 1600 euros the Ryzen 3960X has the triple of scores in passmark benchmark, is that also true for our FEM simulations?

Ryzen 3960X is better in my opinion, for your tasks what you need.

[Slash]

Hi, my workstation has arrived. Unfortunately I have a problem with Abaqus software. The jobs with Abaqus standard solver doesn't run. Instead those with explicit solver work. Do you know any Abaqus limitation/issue with AMD Epyc Rome cpus? The SO is windows 10 pro (not very well supported by supermicro mb).

[flotus1]

So far, I only had the pleasure of using Abaqus on Linux
It can be very picky with the operating system version, but works fine on Epyc Naples. I don't have any Epyc Rome to test. You should definitely contact their support, maybe they know of any hotfix or workaround.
What's the error message in the .log file? Or does it just not start the standard solver without any error messages?

[Slash]

The error that I get is:
The error that I get is:

Abaqus JOB conrod_lin
Abaqus 6.14-5
Abaqus License Manager checked out the following licenses:
Abaqus/Standard checked out 19 tokens from Flexnet server DESKTOP-IAALPTB.
<1005 out of 1024 licenses remain available>.
Begin Analysis Input File Processor
2/19/2020 11:20:36 AM
Run pre.exe
2/19/2020 11:20:43 AM
End Analysis Input File Processor
Begin Abaqus/Standard Analysis
2/19/2020 11:20:43 AM
Run standard.exe
dbghelp.dll not found in PATH2/19/2020 11:20:50 AM
Abaqus Error: The executable standard.exe
aborted with system error code 1073741795.
Please check the .dat, .msg, and .sta files for error messages if the files
exist. If there are no error messages and you cannot resolve the problem,
please run the command "abaqus job=support information=support" to report and
save your system information. Use the same command to run Abaqus that you
used when the problem occurred. Please contact your local Abaqus support
office and send them the input file, the file support.log which you just
created, the executable name, and the error code.
Abaqus/Analysis exited with errors

The error is shows up only with abaqus standard, the explicit solver works fine.

[Slash]

No error messages are present in the .msg and .dat file