cancel
Showing results for 
Search instead for 
Did you mean: 

Processors

cycleback
Journeyman III

Threadripper Pro Memory Bandwidth Specifications?

Are there any official specifications from AMD of the memory bandwidth of the Threadripper Pro processors? Lenovo has released their P620 Thinkstations which features these processors. I can't find any official specifications for the memory bandwidth from AMD or Lenovo.

The only information I could find talking about the memory bandwidth of the Threadripper Pro processors was from CPU world but nothing official from AMD.

https://www.cpu-world.com/CPUs/Zen/AMD-Ryzen%20Threadripper%20PRO%203955WX.html

My workloads are a combination of software that requires both high CPU clock speeds and memory bandwidth (CFD & FEA).

There are Epyc processors with 8 memory channels but reduced memory bandwidths hence my concern.
https://www.servethehome.com/amd-epyc-7002-rome-cpus-with-half-memory-bandwidth/
For instance the Epyc 7252 has 8 memory channels but only a memory bandwidth of 85.3 GB/s (https://www.amd.com/en/products/cpu/amd-epyc-7252) compared to say an Epyc 7302 (https://www.amd.com/en/products/cpu/amd-epyc-7302) with a memory bandwidth of 204.8 GB/s.

0 Likes
3 Replies
arg1
Adept I

I was just wondering this too.   

I suspect the Threadripper Pro 12-core 3945WX and the 16-core 3955WX are contructed like the Epyc 7272 and 7282 that have 4 memory channels from the SoC I/O controller to the cores rather than 8 because of having 4(2?) CCDs per package instead of 8(4?).

I believe that all of these SKUs having a L3 cache size of 64 MB is the evidence.

I just wish I could find reference material from AMD that describes if this is the case.

 

0 Likes

If you haven't yet then check AMD's Technical Documentation webpage from here: https://www.amd.com/en/support/tech-docsScreenshot 2021-02-26 095008.png

0 Likes
arg1
Adept I

Something I came to understand recently is that the Epyc memory bandwidth of 204.8 GB/s is an aggregate value.

The maximum thoughput of a single thread on a core is governed by the Level 3 cache link which is roughly 25 GB/s to memory and 22 GB/s to PCIe (if the infinity fabric is operating at 1600 MHz).    Reaching max throughput for a thread would also require the other cores in a CCX to not interfere.

0 Likes