[otokemo]

Hi guys, this is my second thread in two days, but this issue is related to my office. Since I was looking for a good system for my house, we spoke about it at the office and decided to upgrade our workstations (DELL PT 7810, with 2xE5-2620V4) with something new. It means that we won't need to buy new case, PSU (785W) or GPU.

I saw in another thread, that Mr. @flotus1 recommended the following setup:

CPU: Intel Xeon Gold 6326 (16 cores, 8 channels) | 1025€
Socket 4189 motherboard, e.g. Supermicro X12SPL-F | 570€
8x16GB DDR4-3200 reg ECC | 640€

Which pretty much is inside our budget.
Currently our 2xE5-2620V4 with 96gb RAM have almost the same power as Ryzen 5800x with 32gb RAM (we ran the same Mechanical (FEA) and Fluent (CFD) jobs on both of them). Both FEA and CFD jobs consisted of ~8m elements. Would we get much better power with ~$2000-2500 upgrade, or should we just replace 2620s with something new for the same socket.

[flotus1]

My recommendation you quoted was for a pretty specific use-case. I doubt It would suit your requirements here. By the way, feel free to tell us more about them

Upgrading your old machine with used CPUs could be quite cost-effective. Xeon E5-26xxV4 CPUs are pretty cheap these days.
Such an upgrade should definitely include looking over the memory configuration of this machine. 96GB total hints at an unbalanced memory population at the very least. Which could be part of the reason why it doesn't outperform a Ryzen 5800x.
If I'm not mistaken, your machine has 4 DIMM slots for each CPU. Each of these slots needs to be populated, and all DIMMs should be the same capacity and type.

[otokemo]

Originally Posted by flotus1

My recommendation you quoted was for a pretty specific use-case. I doubt It would suit your requirements here. By the way, feel free to tell us more about them

Upgrading your old machine with used CPUs could be quite cost-effective. Xeon E5-26xxV4 CPUs are pretty cheap these days.
Such an upgrade should definitely include looking over the memory configuration of this machine. 96GB total hints at an unbalanced memory population at the very least. Which could be part of the reason why it doesn't outperform a Ryzen 5800x.
If I'm not mistaken, your machine has 4 DIMM slots for each CPU. Each of these slots needs to be populated, and all DIMMs should be the same capacity and type.

Yes you're right it seems unbalanced but the configuration is following: 4x16gb for on CPU and 4X8gb for another. Does it still mean it's unbalanced?

As for the requirements, we work with FEA and CFD and looking for a suitable system. Since our DELL PT 7810 has a dual cpu motherboard, the power cable is relatively short, since the connector is located on the bottom of the motherboard... but it's a problem for another day.

I was tasked to find a CPU/RAM/Motherboard configuration for ~$2500-3000.
As I understand we would benefit from 8 channel CPU, with 8x32gb or 8x16gb Ram. As well as, we want to understand whatever we can afford with this budget, how much better it will perform than a possible E5-26xxV4 upgrade.

The starting point should be understanding how does our current system pefrorms in Openfoam benchmark. But there also comes FEA part and as I'm aware, FEA is more sensitive with CPU clock than CFD.

[otokemo]

Which software do you intend to use?
Ansys Mechanical, Ansys Fluent

Are you limited by license constraints? I.e. does your software license only allow you to run on N threads?
Nope

What type of simulations do you want to run? And what's the maximum cell count?
FEA and CFD, with 10-20 mil elements and lots of non-linear contacts.

If there is a budget, how high is it?
$2500-3000 for CPU, M/B, RAM
What kind of setting are you in? Hobbyist? Student? Academic research? Engineer?
Engineer.

Where can you source your new computer? Buying a complete package from a large OEM? Assemble it yourself from parts? Are used parts an option?
I have Quadro 4000m, as well as Chasis, PSU and SSD. I'm assembling the rest myselft (Whatever I can utilize from DELL PT 7810)

Which part of the world are you from? It's cool if you don't want to tell, but since prices and availability vary depending on the region, this can sometimes be relevant. Particularly if it's not North America or Europe.
The most East of Europe, we have to buy them from US or some European company.

Anything else that people should know to help you better?

Well, DELL PT 7810 has a specific design, the PSU cable is very short since the MB power connector is at the most bottom of the PCB, it is designed for double socket intel motherboards as I understand. So buying a 2X Xeon would be better, since we would be able utilize chasis, PSU and some accesories. But give me any recommendation.

[flotus1]

Here is the problem with upgrading OEM workstations: you need to know EXACTLY what you are doing.
Form factors could be some weird proprietary stuff. I.e. you won't fit a different motherboard easily.
Same for connectors: The power cables may or may not conform to ATX standards. Both connector types and pinout. And the fans can have connector types you won't find on any normal motherboard.

Dropping in two faster CPUs and upgrading memory is easy. And that's about as far as I would want to go with these things. If you are more adventurous than I am, feel free to try your luck.

I find it difficult to contribute anything helpful at the moment, because you get counterintuitive results with your workloads. I can't comment too much on mechanical, though it is within the realm of possibility that a Ryzen 5800X beats this dual-socket workstation thanks to large single-core segments in your workload.
But the CFD results don't fit. Despite the low-end CPUs, this thing should be significantly faster than a 5800X. The fact that it isn't could be a hint that the simulations you run have some unusual bottleneck. Could be file-I/O, but I just don't know.

[otokemo]

Originally Posted by flotus1

Here is the problem with upgrading OEM workstations: you need to know EXACTLY what you are doing.
Form factors could be some weird proprietary stuff. I.e. you won't fit a different motherboard easily.
Same for connectors: The power cables may or may not conform to ATX standards. Both connector types and pinout. And the fans can have connector types you won't find on any normal motherboard.

Dropping in two faster CPUs and upgrading memory is easy. And that's about as far as I would want to go with these things. If you are more adventurous than I am, feel free to try your luck.

I find it difficult to contribute anything helpful at the moment, because you get counterintuitive results with your workloads. I can't comment too much on mechanical, though it is within the realm of possibility that a Ryzen 5800X beats this dual-socket workstation thanks to large single-core segments in your workload.
But the CFD results don't fit. Despite the low-end CPUs, this thing should be significantly faster than a 5800X. The fact that it isn't could be a hint that the simulations you run have some unusual bottleneck. Could be file-I/O, but I just don't know.

Yup I understand those factors, so I will just keep GPU and I'll buy new chasis and PSU for the system. So keep FEA out of the equation for a second, what would you recommend me otherwise?

[flotus1]

Not sure to be honest.
Xeon E5-2697(A) v4 start around 100€ on ebay these days.
In theory, there is not a lot you could buy new for 3000$ that could beat the CFD performance of two of these in your existing workstation. Along with tidying up the memory situation.
In practice, I don't know if that would do anything, if your current setup is not faster than a Ryzen 5800X for the simulations you run.

[otokemo]

Originally Posted by flotus1

Not sure to be honest.
Xeon E5-2697(A) v4 start around 100€ on ebay these days.
In theory, there is not a lot you could buy new for 3000$ that could beat the CFD performance of two of these in your existing workstation. Along with tidying up the memory situation.
In practice, I don't know if that would do anything, if your current setup is not faster than a Ryzen 5800X for the simulations you run.

I see. Why did you suggest specifically E5-2697A v4? and not 2698 or 2699?

[flotus1]

A quick search on ebay revealed that the 2697v4 and 2697Av4 are fairly cheap. At those prices, it is not really worth considering the lower core count variants.
At the same time, the 18 cores of these CPUs are already excessive. Paying 2x-4x more for even more cores you can't use efficiently, would be a waste of money.

[otokemo]

Originally Posted by flotus1

A quick search on ebay revealed that the 2697v4 and 2679Av4 are fairly cheap. At those prices, it is not really worth considering the lower core count variants.
At the same time, the 18 cores of these CPUs are already excessive. Paying 2x-4x more for even more cores you can't use efficiently, would be a waste of money.

Sounds about right. Thanks! I think we'll upgrade couple of PT 7810s with 16 core E5-26xx v4 cpus, with appropriate Ram, instead of spending all $3000 for one.

[otokemo]

Originally Posted by flotus1

A quick search on ebay revealed that the 2697v4 and 2679Av4 are fairly cheap. At those prices, it is not really worth considering the lower core count variants.
At the same time, the 18 cores of these CPUs are already excessive. Paying 2x-4x more for even more cores you can't use efficiently, would be a waste of money.

Hey Flotus! I bought 8 2697v4s for the office with 128gb Ram for each setup (4 setups in total), but there is a problem with performance, 2xE5-2697As can't outperform 5800x. I opened a new topic in Fluent subforum:
2x E5-2697A performance issues

[Crowdion]

Originally Posted by otokemo

Hey Flotus! I bought 8 2697v4s for the office with 128gb Ram for each setup (4 setups in total), but there is a problem with performance, 2xE5-2697As can't outperform 5800x. I opened a new topic in Fluent subforum:
2x E5-2697A performance issues

To get the best performance you should populate the ram slots correctly. IBM Document in the link below explains the concept of balanced memory configurations

https://lenovopress.lenovo.com/lp050...-configuration