Learning Forum

[piknockyou]

Hi.

Which setup is preferable for Ansys Mechanical running on 4 cores?

Which will result in better performance / faster solution?

8X16 GB RAM or 4x32 GB RAM?

And why?

Mainboard DELL X8DXD with Intel Xeon W-2125 4 Core CPU.

[Hunter Wang]

Refer https://www.dell.com/support/manuals/en-us/precision-5820-workstation/precision_5820_om_pub/memory-specifications?guid=guid-5ee14007-db24-4d37-aecb-34dea3370abb&lang=en-us
and https://www.dell.com/support/manuals/en-us/precision-5820-workstation/precision_5820_om_pub/memory-configuration?guid=guid-ce1561c8-88a9-45e3-bc3b-762cbb37e073&lang=en-us
Both 8X16GB and 4X32 GB should operate at DDR4-2666 MHz for W-2125, should be no difference for memory bandwidth and MAPDL solver performance.
I prefer 4x32 GB RAM. 3 reasons:
almost same price to 8X16GB
1DPC (dimm per channel) configuration usually doesn't downgrade speed, 2DPC may do.
4 DIMMs left for future upgrade

[piknockyou]

Thank you!

[piknockyou]

,please read this:
http://simutechgroup.com/wp-content/uploads/2020/09/maximizing-memory-performance-for-ansys-simulations-2018.pdf
Bottom line: Utilise all memory channels!
Correct me if I am wrong, but in general it seems 8x16GB is better for performance over 4x32GB, isn't it?

Edit: Yes, but only if the mainboard had 8 memory channels. In the case of the mainboard DELL X8DXD following is stated: "4 channel memory up to 256 GB 2666 MHz DDR4 ECC memory with single CPUs on Xeon W Sky Lake Series CPUs".
https://www.dell.com/support/manuals/de-de/precision-5820-workstation/precision_5820_om_pub/memory-specifications?guid=guid-5ee14007-db24-4d37-aecb-34dea3370abb&lang=en-us
Since the Mainboard has only 4 channels, one would only need to make sure, that all of the 4 channels are utilised, either by 8x16GB ignoring any order or 4x32GB necessarily considering the order in the following way:
So thanks again for the links! : )