Low memory speed in Memtest86+ v7

Hi everyone,

I’m running Memtest86+ v7 on my Supermicro H11SSL-i motherboard with an AMD EPYC 7502 CPU. My setup includes 8x MTA36ASF2G72PZ-2G1A2 DIMMs, which are rated at 2133 MT/s but are currently running at 2666 MT/s. However, Memtest86+ is showing a memory speed of only 620 MB/s.

Can anyone help me understand why the memory speed is so low? Is this a normal reading during Memtest86+, or is there a potential issue with my setup?

Thanks in advance for your assistance! :wink:

I’ve seen it change boot-to-boot on my system, but never so low!

If it actually runs through at a normal speed (and passes) it’s probably ok?

For reference, on my AM5 system (7950x) I need about 40 minutes with 96GB of DDR5 6000MTs for one pass. You have more memory but possibly more bandwidth (how many channels do you have?), so I guess you should need about as long? I don’t know how memtest scales though. You have twice the cores, but much less single core performance…

When I run ‘winsat mem’ on a Windows 11 VM with 16 threads and 32GB of RAM (using Proxmox as my hypervisor), I get the following output:

winsat-mem

So… maybe something’s wrong with Memtest86+ v7?! :confused:

When I switched back to NPS1 (instead of NPS4, as suggested in another thread), I noticed a significant improvement, with speeds around 130K MB/s in the VM. However, memtest86+ v7 (are you using the same version?) still takes about 8 hours per pass, which is far longer than the 40 minutes you mentioned… :confused:

Yes, I used the same version.

Might really be an issue with memtest then. Perhaps it is polling ECC, and this is slowing things down? Is there an option to switch this off? Or it has bad support for epyc ?

You could also try another memtest, perhaps the one of passmark?

With MemTest86 it’s a different story altogether! :smiley: