Question Samsung 980 Pro Slow Random Write

Oct 7, 2022
Hello everyone,
I believe I read all topic in the internet about this issue, but I found apparently no solution.
The device performs accordingly to the spec until the random write. Below, the detail of 32k with 16 threads which is the very best I could get:



Here my setup:
MSI X570s Carbonn MAX Wifi
Ryzen 5 5600
64GB DDR2 Ram
Windows 11 fully patched
Bios has been updated to the latest release.
AMD Chipset latest driver installed
Samsung Magician installed, with latest driver for the disk
Cache writing enabled in Windows (Under Disk, Policy)
VBS disabled
Test done after reboot/shutdown/idle for hours.
Tried also with Windows 10 with similar results.

Here is Samsung Magician Driver status detail


This below is the result of a friend of mine, with a very similar setup.

Now, is this a device issue and I better give it back/change brand or somewhere, someone, somehow managed to find a solution?
Thanks for the help
Oct 7, 2022
Yeah the last one is a Beta Version. Wouldn't go there yet. do you suggest I could try that as well?
It is in the first available M2 slot. I also tried it in another PCI Lane (M2.2) but nothing changed.
Oct 7, 2022
Ok I guess I arrived into something.
There is a discrepancy in test enviroument that is substential:
the Ryzen 5600 has 12 threads. Setting CrystalDisk Mark to use 16 Threads makes no sense. Actually it is very damaging, because I believe the CPU needs to queue and buffer information to properly meet 12 threads I/O processes. This might clog the CPU cache and performs poorly.
In fact, setting Crystal Mark to 12 Threads gets me up to 4000 MB/S.
You might not have the same issue on Read, because the CPU input for the disk does not need to queue anything: it just query the disk for as much as 12 threads can get (4000/4500MB/s) and delivers over 16 threads line of CrystalMark.

I''ve never found this information anywhere.
In my case, there is the following conclusion:

In order to provide the best performance on Random Write, always sync the number of CPU Threads with the number of Crystal Mark Threads.

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