Dual Epyc workstation questions

[Quartz]

My brother is looking at a dual-Epyc workstation (2x 64 cores, 256 GB+ RAM, £20k+) and I'm looking to better advise him, so have a few questions.


First, how much is the performance difference between quad-channel and octo-channel RAM?
Second, how much is the added latency of one CPU accessing RAM associated with another CPU?
Third, he's looking at the Supermicro H12DSi-NT6. Any thoughts?

He's also looking at an American company to build it which is a big red flag from a RMA / support POV. This isn't OCUK's usual fare so I'm going to post in the customer support forum (OCUK staff click here) to see if they will before asking for other sources.

 

[Quartz]

I've put him in touch with OCUK as a possible builder.

 

[Quartz]

Something doesn’t quite add up here.

It actually does add up for the tasks he wants to run: 8 sessions of an application which uses 16 cores and 32 GB RAM for each session. I.e. 128 cores and 256 GB RAM. Hyperthreading / SMT is strongly discouraged for this application.

They also usually require a level of support/warranty that includes an SLA on hardware repairs that would have any sane individual scratching his/her head as to why they would have it supplied by a US firm.

I have already pointed this out to him. As I said, it's a big red flag.

Anyway, OCUK are on the case and I'm sure I will be hearing about it soon enough.
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