Question Samsung SSD Speed after 48 hours

Apr 10, 2021
Hi, I'm new here.
I bought an 8TB Samsung 870QVO a few weeks ago.

I have had an awful experience trying to copy files on to this drive. It takes forever.
After 48 hours it only managed 3TB.
I'm sure my 5400RPM drives perform better than this.

Initially with CrystalDiskMark it was reporting reading and writing speeds of about 400 Mbps with an external USB3.1 case.

After 4 hours of waiting for it to copy, i cancelled and checked the speed again. And it had gone down to 40 Mbps.

This is probably the 5th or 6th time Ive attempted to copy these files. All the other times, something dubious has occurred (e.g. disk can't be read), so i've had to go into DISKPART to CLEAN the drive, format and start all over again. And i feel it is getting slower and slower (in just the few weeks i've had it)

Is this a dud drive? Or is this regular SSD behaviour?

I understand that heat can impact performance, but after 48 hours, the case and the drive are reasonably cool (Not even warm).

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it might be your usb enclosure fault..well it depends
that drive eats 5.5watts, usb3.x gen 1 can provide 1amp on 5v, which is 5watts (slightly less than drive needs)
if your usb enclosure has external power supply, or its gen2, u should be fine

see if drive cache is enabled, it might be disabled for external (usb) drive
go to device manager, find your drive there and enable write cache
Apr 10, 2021
Oh. thanks. Will try again with Write-Caching.

Have uploaded images now.

(Trying to) transfer thousands of Audio WAV files and samples.

Have 3 different enclosures. All 3 seem to slow down after time.

The source drive is an HGST 12TB 7200RPM drive in a WD Black USB3 Enclosure.
Apr 10, 2021
so i moved the hard disks over to a different computer to continue the copying.

speeds were MUCH faster. so i left it going overnight.
However, in the morning, the SSD was inaccessible (AGAIN!).
This time, Windows told me it was a cyclic redundancy error.
So i'm running CHKDSK on it now.

Is there any fool-proof way to verify the health of this disk so i can know for sure whether it needs to be sent back (or not)?

I'm also skeptical about my WD_Black drive. According to CrystalDiskMark it performs way better than my internal 5400 HDD drives. But my m1 Macbook doesn't like it at all. I'm using Paragon NTFS and it's fine with other NTFS drives. On Mac, it spends an eternity trying to read the drive, let alone start copying.
Apr 10, 2021
This seemingly simple attempt to transfer files has already consumed copious amounts of time.
Any advice on a workaround?
First of all, the QVO is a budget SSD that is oriented to fast reading, not writing.
When you copy a lot of data to the QVO, or any SSD for that matter, the write buffers will eventually fill up and writing can go no faster than the speed of the underlying nand chips.
The chips on the QVO are slower, but also cheaper.
Not much you can do about this.
If you can arrange to do the copy a little bit at a time with a pause between sets, it will allow the device to clear the buffers.
USB connection will be slower than a simple sata connection.
What are you putting on this 8tb ssd?
If it is for backup and this is the initial backup, bite the bullet and take the time it needs.
Subsequent incremental backups will write less data.
Or, use a 8tb HDD.
Sequential writes to a HDD go reasonably fast.

FWIW, I recently used the samsung ssd migration aid to copy about 500mb to a 860 EVO connected via usb3.1
It took about 4 hours.
When I subsequently attached the 860 EVO as a sata drive and copied back to a samsung 980 Pro device and pcie 4.0,
it took 30 minutes.
Apr 10, 2021
I'm ok with it being a budget drive. It fulfills it's purpose as a library. Once it's full it will only be read from.

I gave up on the CHKDSK. It was going to take 24 hours. So cleaned and formatted again.

As you mentioned, have taken the SSD out of the USB enclosure, now have it hooked up inside a 12 year old PC, using the (not very good) Marvell 9128 SATA3 controller. Have left it running for a few hours, and its running a lot faster, and more in-line with the read speeds of the HDD (at about 100-185 MB/s).

Just hope all this writing hasnt caused any long term damage to the SSD. Because even a budget 8TB SSD ain't cheap!

Will multiple instances of copying from one drive to another cause errors? I suspect it will cause the HDD (source) to go mental as it struggles to move around the platter.
Any SSD will have nand blocks that have a limited number of writes.
Something like 10,000 or so for each block.
I think your 9tb QVO can handle 2880TB of writes.
But, a 8tb SSD will have a HUGE number of such blocks so you will not run out of updates.
Not to worry; Your first attempt has done no damage to the drive.
Samsung magician and other apps will tell you the status of the drive.
Magician can also run diagnostics and even update firmware if it were necessary.
I do not keep magician installed. It is one of those apps that feels the need to always call home in case there might be an update or such.

A HDD is remarkably good when doing one thing at a time sequentially.
That keeps the access arm positioned where it should be giving minimal latency.
OTOH, if you are copying from one part of a single drive to another the arm will constantly be in need of repositioning and your copy may be 10x longer than from one drive to a second.