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[NVMe] Poor RND4K Write IOPS and μs on 2/3 drives

Zelevas

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Aug 1, 2021
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I thought I'd do a benchmark of my SSDs to compare with a friend and I've noticed that for an unexplained reason, 2 out of 3 of my NVMe SSDs are suffering from really terrible RND4K write IOPS with a terrible latency on top.

10700K
Z490 Aorus Ultra - F20

Drives (In order of the screenshot)
980 Pro 1 TB
MP Force 510 1 TB
MP Force 510 1 TB

I've tried rotating SSD placement on my motherboard with 0 luck, I've reformatted windows since doing the original run and nothing has changed. I've got the latest BIOS, have reset my BIOS to factory setting to test, updated firmware for all SSDs and there has been 0 improvement. I've also tried only having a singular SSD in at any given time, removed SATA drives and tested the SSDs in both hot and cold working conditions.

What confuses me is that one of the MP Force 510 drives is displaying the same slow-down issue as the 980 Pro, whereas the second MP Force 510 is working perfectly fine. I've even installed modified 980 Pro drivers across all SSDs with no change.

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@Zelevas Hello and Welcome to the Tech Power Up Forum!

First of all, have you tried "TRIMing" the drive? Use samsung magician.
And which M.2 header on your motherboard are you using it?
Because the "M2P_SB" and the "M2M_SB" are wired directly to the Chipset "PCH" so naturally it WILL have higher latency.

What could be happening as well, although i doubt it, is the Samsung's Turbo Write didn't allocate enough space for this test because it didn't have time to recover yet, since this pSLC Caching is all Dynamic, it shrimks as you fill up your drive, so it has less and less space available. But i don't think that's it.
 
The 980 Pro is attached to the slot M2M_SB. I believe I tried it in M2A_CPU without change, but I'll give it a shot of swapping it to the M.2 slot wired to the CPU for re-assurance. I have tried trimming and overprovisioned by roughly 5% (Enough to make the SSD have a clean "900GB" in Explorer). This test was done through a fresh OS installation, but I'll update my comment further once I've had the chance to rotate drive placement. Thanks for the help so far.

Swapped it around to M2A_CPU and both of the swapped drives are now performing worse. The only thing I noticed is that the 2 drives I rotated now list as SCSI Disk Device in both task manager and device manager
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The 980 Pro is attached to the slot M2M_SB. I believe I tried it in M2A_CPU without change, but I'll give it a shot of swapping it to the M.2 slot wired to the CPU for re-assurance. I have tried trimming and overprovisioned by roughly 5% (Enough to make the SSD have a clean "900GB" in Explorer). This test was done through a fresh OS installation, but I'll update my comment further once I've had the chance to rotate drive placement. Thanks for the help so far.

Swapped it around to M2A_CPU and both of the swapped drives are now performing worse. The only thing I noticed is that the 2 drives I rotated now list as SCSI Disk Device in both task manager and device managerView attachment 211412
Ok, which BIOS revision have you been using it? and how it have the lastest firmware on each drive?
 
F20. Used Magician and Corsair Toolbox to update Firmware to the latest.

Also this might be slightly embarrassing to admit, but I believe I found the cause of the problem and it's a dumb thing on my end. I've been running Windows 11 Insider Preview so that I can test out some applications compatibility and the CrystalDiskMark tests I've been doing have also been ran from within Windows 11. I reformatted the drive with a clean Windows 10 installation and all 3 NVMe drives ran at their designed speed without any issue. The second I updated to Windows 11, the drives started performing poorly on the writes.

Given that I now know what the root cause of the issue is (or may be), I can at least report the issue on Reddit and Microsoft's Feedback Hub to see if there's any OS workaround or if it's something they'll fix at a later date.
 
F20. Used Magician and Corsair Toolbox to update Firmware to the latest.

Also this might be slightly embarrassing to admit, but I believe I found the cause of the problem and it's a dumb thing on my end. I've been running Windows 11 Insider Preview so that I can test out some applications compatibility and the CrystalDiskMark tests I've been doing have also been ran from within Windows 11. I reformatted the drive with a clean Windows 10 installation and all 3 NVMe drives ran at their designed speed without any issue. The second I updated to Windows 11, the drives started performing poorly on the writes.

Given that I now know what the root cause of the issue is (or may be), I can at least report the issue on Reddit and Microsoft's Feedback Hub to see if there's any OS workaround or if it's something they'll fix at a later date.
Hahah LoL tbh i didn't even remember to ask that but yeah that's why it's npt been release yet
 
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