[mike7877]

The system that the 980 is in uses Intel's z390 chipset - its NVMe slot supports up to 4,000MB/s sequential.

Below this writing is screenshots of a couple CrystalDiskMark (CDM) runs I ran on both of the system's currently installed SSDs: a 980 Pro (250GB) and 970 Evo Plus (1000GB). Below them is the total reads and writes (in GB) from new. Also 980 top/970 bottom.

What could possibly be the cause of this pretty extreme reduction of write speed? So much has been lost, leaving just 580MB/s in the very best case.
I think performance decreased gradually. Not very very slowly, over a long long span of time, but about 3 weeks ago I noticed sequential writes were around 20% slower than usual. Now I have only 20% left!!

 

[Blameless]

It's 82% full and SLC write cache size is generally set to a fraction of remaining capacity. If you've been writing any significant amount of data recently, the SLC cache could easily be exhausted.

You probably crossed some capacity threshold that caused the firmware to kick down the SLC cache size significantly, or reached some critical fragmentation threshold that garbage collection is having an issue dealing with.

 

[mike7877]

It's 82% full and SLC write cache size is generally set to a fraction of remaining capacity. If you've been writing any significant amount of data recently, the SLC cache could easily be exhausted.

You probably crossed some capacity threshold that caused the firmware to kick down the SLC cache size significantly, or reached some critical fragmentation threshold that garbage collection is having an issue dealing with.

I haven't been writing a lot, probably 20GB per day over the last week or two.

I think the biggest file on the drive is a Windows 10 Pro x64 ISO, and everything else is 2GB tops.

I typed defragment into the start menu and got this. Clicked Optimize, now have this:

Doesn't seem to have changed anything.

Is there a way to force garbage collection?

It's only a bit early for my semi-annual reinstallation of Windows. I like to keep things fresh, and most of the programs I use can export their configurations, and the ones that can't aren't a horrible pain to reconfigure. A reload would likely solve my problem? If so, I can push up the date

 

[Offler]

Try command 'bcdedit -enum'.

Is usedplatformclock enabled or disabled? For my system enabled means significant decrease of IOPS and also it would not affect just one drive but both.

There could be something going on PCI-E slot...

 

[zayd]

I'm using a 980 pro 1TB on a Z390 motherboard also and this SSD is about 75% full, yet it still gets the expected level of speed when reading and writing. You may have inadvertently clipped the speed of your NVME slot by using one of the other drives. Check your motherboard manual and see if this is the case and reference back to all your plugged in drives.

 

[mike7877]

Try command 'bcdedit -enum'.

Is usedplatformclock enabled or disabled? For my system enabled means significant decrease of IOPS and also it would not affect just one drive but both.

There could be something going on PCI-E slot...

Where would I check usedplatformclock?

PCIe slot even though read speed is full?

 

[mike7877]

I'm using a 980 pro 1TB on a Z390 motherboard also and this SSD is about 75% full, yet it still gets the expected level of speed when reading and writing. You may have inadvertently clipped the speed of your NVME slot by using one of the other drives. Check your motherboard manual and see if this is the case and reference back to all your plugged in drives.

It used to run full speed with my board configured this way. I'll go over its configuration though: I only have two NVMe drives installed right now. 980 uses dedicated PCH lanes, 970 uses some dedicated and some of SATA (disables SATA 5 and 6). The x4 slot that I've used in the past for a third NVMe drive is now used for a 20Gbps USB 3.2 Gen 2x2 controller, but I've been using it in another system for the past month so the slot is empty. Only one x1 slot is taken and that's by a SATA RAID card (just two ports, RAID 0 or 1)

 

[zayd]

Can you swap the two NVME drives around to eliminate a faulty slot?

 

[mike7877]

Can you swap the two NVME drives around to eliminate a faulty slot?

Will it screw up secure boot?

 

[Asmodian]

Will it screw up secure boot?

No, not unless you are doing something very non-standard. Did you use custom keys or anything like that?

 

[mike7877]

No, not unless you are doing something very non-standard. Did you use custom keys or anything like that?

I created a virtual TPM for when I eventually install Windows 11. I don't remember exactly what I did, but it wasn't too involved. If custom keys need to be exported and imported (like I think I'm remembering they do), then I didn't

 

[Asmodian]

Sounds good, that will all be fine if you move drives around.

 

[ozlay]

Have you updated to the latest firmware? Not sure what OS you are running. But if i remember correctly there was a windows 11 bug that cut the 980 pros speed in half. But it was fixed with a firmware update. I believe the 980 pro has had a bunch of firmware updates. But some of them just fixed PS5 performance. I believe 5B2QGXA7 was the firmware that fixed the windows 11 bug.

 

[mike7877]

Have you updated to the latest firmware? Not sure what OS you are running. But if i remember correctly there was a windows 11 bug that cut the 980 pros speed in half. But it was fixed with a firmware update. I believe the 980 pro has had a bunch of firmware updates. But some of them just fixed PS5 performance. I believe 5B2QGXA7 was the firmware that fixed the windows 11 bug.

I didn't realise my OS isn't in my sig. I'm running Windows 10 Pro x64 for the time being. I'll be switching to 11 when mainstream support ends for 10. I have Windows 11 on my laptop, and certain things about it just irk me. For example, not being able to right click on the task bar to open task manager. I had to find it, run it, then pin it to the taskbar. Waste of space... There are at least a dozen other things that are just as annoying. But this isn't a ***** about Windows 11's quirks thread so I won't get into them. I'm slowly getting used to 11 with my laptop - hopefully I'm used to it by the time 10 is dead.

If it's only with Windows 11 that firmware causes issues, I think I'll leave it for now. I'm going to reload Windows - if I get a second wind I might start the process tonight!

 

[Blameless]

Is there a way to force garbage collection?

You can try overwriting the drive's free space, but the TRIM function of the Windows' Defragment and Optimize drives shouldn't be that different, in practice.

An actual defragmentation might be worth a shot. As you're probably aware, it's typically not recommended on SSDs because there is no positional advantage to access times and it burns a lot of P/E cycles. However, file and free space fragments still need to be tracked on the NTFS bitmap and a badly fragmented file system can cause excess overhead even on an SSD. It may well not help, but the rare degfragmentation isn't going to burn enough P/E cycles to hurt much either.

A reload would likely solve my problem?

Yes, but only because a quick format would empty and force a retrim of the whole drive. As soon as the drive got this full again it would likely behave similarly.

As has been suggested, updating the SSD's firmware might help.

 

[mike7877]

You can try overwriting the drive's free space, but the TRIM function of the Windows' Defragment and Optimize drives shouldn't be that different, in practice.

An actual defragmentation might be worth a shot. As you're probably aware, it's typically not recommended on SSDs because there is no positional advantage to access times and it burns a lot of P/E cycles. However, file and free space fragments still need to be tracked on the NTFS bitmap and a badly fragmented file system can cause excess overhead even on an SSD. It may well not help, but the rare degfragmentation isn't going to burn enough P/E cycles to hurt much either.



Yes, but only because a quick format would empty and force a retrim of the whole drive. As soon as the drive got this full again it would likely behave similarly.

As has been suggested, updating the SSD's firmware might help.

I've had this drive very full, things could be very fragmented... I'll defragment and then make a bunch of copies of my windows 10 disc image til it's full

 

[mike7877]

Well, this is what Windows Defragmenter looks like now. No option to defrag!

 

[Blameless]

Well, this is what Windows Defragmenter looks like now. No option to defrag!

That's normal; Windows won't let the defrag utility defragment drives reported as SSDs.

You'll want to use a 3rd party tool (almost all of which still use the Windows defrag API), like ultradefrag (7.1.4), defraggler, etc.

 

[Offler]

Where would I check usedplatformclock?

PCIe slot even though read speed is full?

If its not listed there, its default eg. disabled and not causing the problem.

Have you tried Samsung Magician?

 

[Dziarson]

Bla bla bla Samsung 980 Pro 1TB Slow Write Speeds / Samsung SSD 980 PRO extreme slow write speed (1100 mb/s) i heve 980Pro slow writing speed is Samsung's fault, something they failed 3 firmware is still the same, I solved the problem simply, I bought KC3000
as not system drive samsung is working fine.