[SOLVED] Slow memory bandwidth on Xeon-D

Hello friends and level1tech heads!

I have a Supermicro board with a xeon-d 1537 (X10SDV-7TP4F). And during my “torture test”, I noticed my MEM bandwidth to be a little lackluster:

Maybe memtest is not the best to test memory bandwidth, but when I looked at older xeon E3’s it seemed they had atleast twice that bandwidth. Around 20GB/s in the same test.

I thought it might have something to do with the slower clock speeds of the xeon, but according to this sites math, they do not include anything CPU related in the equation: https://www.pcsteps.com/7932-real-ram-speed-mhz-cas-latency/

They do talk about having dual channel or even quad channel - and when I google around it doesn’t seem that this board has anything of the sort. Is this the source of my lackluster memory bandwidth?

Maybe its a bit too late, and my google-fu has failed me so I’ve missed something. Do any of you guys have a good explanation or a suggestion as to why the memory of my system seems to be “slow”?

Thank you and kind regards
Liq

I have an increasing suspecion it is because a lack of dual/quad channel memory :frowning:

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Tried testing with different memory configurations and did see a very small change in the bandwidth

1 DIMM
memtest-1dimm

2 DIMM

So I started digging a bit deeper in the Manual: http://www.supermicro.com/manuals/motherboard/D/MNL-1858.pdf

The motherboard diagram shows the memory being connected to the CPU in pairs. Also when you start reading more about memory configuration Supermicro recommends installing memory in “kits of two” as it will “increase performance”. However they never mention dual channel, they do mention interleaving. So apparantly there is no support for dual/quad channel memory.

So the question I am left with now: Is dual/quad channel memory a consumer feature, which is not available to ECC? Or is it a limitation of the Xeon SoC / Supermicro board?

So apparently it was a fluke on memtest86 part - for whatever reason. If I test with AIDA64 and check with CPU-Z I get the following results: