[rr3245]

I am looking to build a desktop for OpenFOAM CFD simulations. I have access to HPC facilities, but I want this desktop to be able to handle 1-10 million cells. At work I run desktop simulations on 4 cores/4 threads, but I’d like to build something better than this, 8 cores/16 threads if possible. I’ll use it for basic post-processing in paraview too. I run mostly transient LES.

This is my first PC build and I’m far from computer/tech savvy, so please bear with me. I have shamelessly copied a great deal from the following thread: Budget desktop/workstation build. My preliminary research into a PC build has led me to the build below. This comes to around £1300, which is well over my max budget of ~£800. I am unsure how this all fits together. Are there any components which are way out of whack with the rest? Thanks in advance.


CPU- Intel Xeon E5-2690, 2.9 GHZ, 8 core, 16 threads, 4 memory channels.

RAM- KINGSTON 32GB Kit (4 x 8GB) HyperX Predator DDR4 3200MHz, CL16, Black, DIMM Memory

Cooler- Special NOCTUA NH-D15S, 160mm Height, 220W TDP, Copper/Aluminum CPU Cooler

Motherboard- ASROCK X299 Extreme4, Intel X299 Chipset, LGA 2066, ATX Motherboard

Graphics- EVGA GeForce GTX 1060 SC GAMING ACX 2.0, 1607 - 1835MHz, 6GB GDDR5, Graphics Card [VR-Ready]

Storage- SAMSUNG 500GB 860 EVO 7mm, 550 / 520 MB/s, V-NAND MLC, SATA 6Gb/s, 2.5-Inch SSD

PSU- SEASONIC SSR-750PX, 80 PLUS Platinum 750W, Fully Modular, ATX Power Supply

Case- Meshify C, No PSU, ATX, Black, Mid Tower Case

[flotus1]

It is a good start, but some of the parts are not compatible. On top of most of the components being a bit too pricey for £800 total.
While the Xeon E5-2690 CPU is still a valid option for a budget CFD build since it is cheap second hand and dual-socket capable, it came out in 2012 for Socket 2011. It won't be compatible with an X299 motherboard or DDR4 memory.
With a budget of £800 pounds, you probably don't want to get into current gen HEDT territory. That stuff is expensive.
First thing I would do is check if the budget allows for a significant improvement compared to your current quadcore workstation. So we would need more information about this machine first.

[rr3245]

Thanks for the quick reply, flotus1.

My current work PC is:

CPU: Intel® Xeon(R) CPU E3-1225 v3 @ 3.20GHz × 4
Motherboard: ASUS P9D WS
Graphics: Quadro K620/PCIe/SSE2 (2 GB, DDR3 SDRAM)
RAM: 16GB (can't find any more info on this).

I can't run lshw -short because I am not super-user. Therefore I will have to ask someone in IT for more detail.

In order to bring the build down below £1000, I would be happy to sacrifice some performance from my original list/post. However, if I go this route, it would like to have the option to upgrade at a later date if necessary. So a cheaper build with the capacity for upgrading in the future would suffice.

Cheers.

[flotus1]

Upgradeability for CFD workstations is a bit difficult. Once you chose a platform, your performance ceiling is set. Depending on your choice you may be able to swap CPUs in a few years and get more cores or slightly faster clock speeds. Neither of which is particularly helpful when computing at the memory bandwidth limit.
In order to get a real upgrade you will have to change at least the motherboard, CPU and RAM.

That being said: your best price/performance option is probably LGA 2011-3 with an X99 chipset. This would require sourcing the CPU and the motherboard from the second hand market. Plenty of people are currently selling these, so there should be ample supply.

Approximate prices in €
CPU: I7-5820k 130€
Motherboard: some ATX X99 <100€
RAM: 4x8GB DDR4-3000 or faster 250€
Power supply: something in the 500W range, e.g. Seasonic Focus Plus Gold 550W 75€
Case: Some ATX case in the 70€ price range with enough space for a decent CPU cooler. E.g. Fractal Design Define S
Cooler: Some air cooler in the 40€ price range
SSD: Samsung 860 Evo 500GB 85€
Graphics card: GTX 1030 GDDR5 or for example a used GTX 750TI 2GB for 60€
And as much HDD space as you need.
You might as well consider a larger SSD depending on the file size that your transient simulations produce.

You will also find lots of bundles containing motherboard+CPU+Cooler+RAM or any combination of that which can be a good bargain.
I don't see any other way to get a workstation that is significantly faster than what you already have. And it will be upgradeable in the sense that you have standard components with decent quality. So you will be able to keep most of them and change motherboard/CPU/RAM later.

[rr3245]

Originally Posted by flotus1

Upgradeability for CFD workstations is a bit difficult. Once you chose a platform, your performance ceiling is set. Depending on your choice you may be able to swap CPUs in a few years and get more cores or slightly faster clock speeds. Neither of which is particularly helpful when computing at the memory bandwidth limit.
In order to get a real upgrade you will have to change at least the motherboard, CPU and RAM.

That being said: your best price/performance option is probably LGA 2011-3 with an X99 chipset. This would require sourcing the CPU and the motherboard from the second hand market. Plenty of people are currently selling these, so there should be ample supply.

Approximate prices in €
CPU: I7-5820k 130€
Motherboard: some ATX X99 <100€
RAM: 4x8GB DDR4-3000 or faster 250€
Power supply: something in the 500W range, e.g. Seasonic Focus Plus Gold 550W 75€
Case: Some ATX case in the 70€ price range with enough space for a decent CPU cooler. E.g. Fractal Design Define S
Cooler: Some air cooler in the 40€ price range
SSD: Samsung 860 Evo 500GB 85€
Graphics card: GTX 1030 GDDR5 or for example a used GTX 750TI 2GB for 60€
And as much HDD space as you need.
You might as well consider a larger SSD depending on the file size that your transient simulations produce.

You will also find lots of bundles containing motherboard+CPU+Cooler+RAM or any combination of that which can be a good bargain.
I don't see any other way to get a workstation that is significantly faster than what you already have. And it will be upgradeable in the sense that you have standard components with decent quality. So you will be able to keep most of them and change motherboard/CPU/RAM later.

Thank you for your help. I'll scale my expectations/budget back. I've started looking for second hand CPUs and motherboards. Will report back once I've done some more research. Thanks once again.