SanDisk 2TB Extreme Portable V2 SSD seem to be getting half speed on USB 3 ports

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Tanquen

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I got a new SanDisk 2TB Extreme Portable SSD and it seems to be getting half the USB 3 speed.

On a Gen 1 port I get 300MB/s but I thought I should be getting around 600MB/s. On the Gen 2 port I do get 600MB/s but shouldn't it be over 1GB/s?

USB 2.0April 2000High Speed, also Hi-SpeedHS480 Mbit/s (60 MB/s)
USB 3.0*November 2008SuperSpeedSS5 Gbit/s (625 MB/s)
USB 3.1 Gen 2July 2013SuperSpeed+SS+10 Gbit/s (1.25 GB/s)
 
Tanquen said:
I got a new SanDisk 2TB Extreme Portable SSD and it seems to be getting half the USB 3 speed.

On a Gen 1 port I get 300MB/s but I thought I should be getting around 600MB/s. On the Gen 2 port I do get 600MB/s but shouldn't it be over 1GB/s?

USB 2.0April 2000High Speed, also Hi-SpeedHS480 Mbit/s (60 MB/s)
USB 3.0*November 2008SuperSpeedSS5 Gbit/s (625 MB/s)
USB 3.1 Gen 2July 2013SuperSpeed+SS+10 Gbit/s (1.25 GB/s)
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Just because you're plugged into a port does not mean you're actually getting a link at the appropriate speed. I'd plug into the port yo uonly get 300 MB/s on and run HWInfo64 and see what the actual link speed is. USB cables can be picky too.
 
It comes with a very short cable and I did try another just for fun. If USB 3 (the slow version) Gen 1 should be 625MB\s it seem like I should be getting a bit closer that 50%.

It's not a USB 2 port and it's not getting USB 3.0 speeds, what is it? Did Gigabyte mess up there USB 3 ports?
 
Well the speed you should expect us closer to 500MB/s just because the internal drive is SATA but I get your point. Checking the link speed is the best starting point.
 
No, I think it's NVMe as it advertised as upto 1050MB\s and some folks that have it say they are getting 950 MB\s. I get 600MB\s on the motherboards Gen 2 (2x1) USB C port.
 
check inside windows to make sure it isnt in quick removal mode. fund my 960 pro to be running 985mbs+ after that change.
 
Just a little underwhelmed, I know tech storage is about lying as much as you can (1000GB is a TB, 1024GB is not a flippin TiB!) about speed and size but this was even less than I expected.

Today it's faster???

The Gen2 port is now getting around 820MB/s copying a large vhdx file from it. CrystalDiskMark says its read is 1000MB\s at 1 MiB sequential but the CrystalDiskMark Read heading says MB/s so that is not real MB\s so that is why the windows copy status window shows a much lower max read of 820(real)MB/s?

My Samsung T5 is a Gen 1 device and on a Gen 2 port it's CrystalDiskMark is 567MB\s and it's Windows file copy is around 510MB\s. So I was think the Gen 2 SanDisk would be a lot closer to 1GB\s.

The T5 on the Gen 1 port gets a CrystalDiskMark of 446MB\s and it's Windows file copy is around 410MB\s.

The SanDisk on the Gen 1 port gets about the same.
 
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Shadowarez said:
check inside windows to make sure it isnt in quick removal mode. fund my 960 pro to be running 985mbs+ after that change.
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But then that is not the real write speed it's the cached speed. I'd rather know that the file is done when the copy status window is.
 
Tanquen said:
But then that is not the real write speed it's the cached speed. I'd rather know that the file is done when the copy status window is.
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I mean, there is a reason people uses caches; it's faster. And it's not pretend speed, it's real speed. If you're worried about writes not being done just don't yank the damn drive out the moment the status bar finishes copying, and use safe removal.
 
sinisterDei said:
I mean, there is a reason people uses caches; it's faster. And it's not pretend speed, it's real speed. If you're worried about writes not being done just don't yank the damn drive out the moment the status bar finishes copying, and use safe removal.
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I'm trying to find the real read/write performance.

Cache is just not worth it, to me. It's not real speed to me and runs out on larger stuff when I would actually want the speed. I'm copying stuff and want to leave when done not use the portable drive as a working drive. I also don't just yank damn drives.
 
file size matters. copying a bunch of small files will result in a slower write speed as windows verifies every file after it writes it. large files like movies will have a higher continuous write speed.
 
Zepher said:
file size matters. copying a bunch of small files will result in a slower write speed as windows verifies every file after it writes it. large files like movies will have a higher continuous write speed.
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That's why I was testing with a large single file. If you have a folder with thousands of various sized files then yeah here read write speed will be all over the place and usually super super slow.
 
What's the motherboard you're using? Reading that board's spec sheet should help.
 
trandoanhung1991 said:
What's the motherboard you're using? Reading that board's spec sheet should help.
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In me sig: Motherboard: GIGABYTE X570 AORUS Xtreme

Again I think its just the USB overhead (and or the MB vs. MiB BS) and I've not really looked at USB in some time. I have a Lexar that was the fastest USB flash at the time and it's around 250MB\s then I have been using a Samsung T5 for the last year or so and it's around 400-500MB\s and I just though a USB 3 Gen 2 device rated at 1050MB\s would be lots faster. It's not really much faster than the T5.

At first, for some unknown reason I was only getting 300MB\s on a Gen 1 port and then 600MB\s on a Gen 2 port but I now get 820MB\s on the Gen 2 and that is better but I was thinking I'd get the Real 900-1050MB\s.
 
Tanquen said:
In me sig: Motherboard: GIGABYTE X570 AORUS Xtreme

Again I think its just the USB overhead (and or the MB vs. MiB BS) and I've not really looked at USB in some time. I have a Lexar that was the fastest USB flash at the time and it's around 250MB\s then I have been using a Samsung T5 for the last year or so and it's around 400-500MB\s and I just though a USB 3 Gen 2 device rated at 1050MB\s would be lots faster. It's not really much faster than the T5.

At first, for some unknown reason I was only getting 300MB\s on a Gen 1 port and then 600MB\s on a Gen 2 port but I now get 820MB\s on the Gen 2 and that is better but I was thinking I'd get the Real 900-1050MB\s.
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I found the issue.

As per https://shop.westerndigital.com/en-...isk-extreme-pro-usb-3-2-ssd#SDSSDE81-2T00-G25, this drive is rated at 2000MB/s on USB 3.2 Gen 2x2, i.e. 20Gbps interface. With Gen 2 single, you're effectively getting half the promised performance.

You'll need Thunderbolt 2 or USB 3.2 Gen 2x2 to get the full performance of that drive (not 100% sure on TB2 or TB3, in theory TB2 should be sufficient), which your MB doesn't support.
 
trandoanhung1991 said:
I found the issue.

As per https://shop.westerndigital.com/en-...isk-extreme-pro-usb-3-2-ssd#SDSSDE81-2T00-G25, this drive is rated at 2000MB/s on USB 3.2 Gen 2x2, i.e. 20Gbps interface. With Gen 2 single, you're effectively getting half the promised performance.

You'll need Thunderbolt 2 or USB 3.2 Gen 2x2 to get the full performance of that drive (not 100% sure on TB2 or TB3, in theory TB2 should be sufficient), which your MB doesn't support.
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????

No, I have the one that is rated at 1050MB\s, not the Pro V2 or whatever. Too much money and I'll not see a Gen 2 2x2 port in the wild for many years I'm guessing. Seen a few project workstations with Gen 2 2x1 and it's nice to have.

The USB 3 Gen 2x1 should be fine. Maybe on a Gen 2x2 port I'd get closer to 1050MB\s vs. the real world real MBs of 820MB\s. Again, when I first posted I was getting like 600MB\s and still do not know why.

USB 3 is a mess, it's 3.0 no 3.1 no 3.2 that is the same as 3.1 with some new 2x1-2x2 options.

Then there is the whole we as drive manufactures like to lie and put the biggest number on the box thing so even though the operating systems used by 99.9% of our customers say a MB is 1024k we says its 1000k so we can put bigger numbers on the box. Then there is formatting and so on and your new 14TB drive is really 12TB. Now I guess there are (or have been) doing the same with speeds, so your new 1050MB\s drive will never see that speed with overhead and the lie that is MB vs. MiB means you'll end up with 820-ish MB\s not 1050MB\s.
 
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Tanquen said:
????

No, I have the one that is rated at 1050MB\s, not the Pro V2 or whatever. Too much money and I'll not see a Gen 2 2x2 port in the wild for many years I'm guessing. Seen a few project workstations with Gen 2 2x1 and it's nice to have.

The USB 3 Gen 2x1 should be fine. Maybe on a Gen 2x2 port I'd get closer to 1050MB\s vs. the real world real MBs of 820MB\s. Again, when I first posted I was getting like 600MB\s and still do not know why.

USB 3 is a mess, it's 3.0 no 3.1 no 3.2 that is the same as 3.1 with some new 2x1-2x2 options.

Then there is the whole we as drive manufactures like to lie and put the biggest number on the box thing so even though the operating systems used by 99.9% of our customers say a MB is 1024k we says its 1000k so we can put bigger numbers on the box. Then there is formatting and so on and your new 14TB drive is really 12TB. Now I guess there are (or have been) doing the same with speeds, so your new 1050MB\s drive will never see that speed with overhead and the lie that is MB vs. MiB means you'll end up with 820-ish MB\s not 1050MB\s.
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Ah sorry, I read Portable as Pro for some reason.

If you're getting 800MB/s you're getting better than what Tom's get https://www.tomshardware.com/reviews/sandisk-extreme-v2-portable-ssd-review/2

It's possible that 1000MB/s rated is for the top dog 4TB version, since AFAIK performance do go up with capacity.
 
You'll never get the theoretical top speed when copying files in the OS.

Use CrystalDisk to check that everything is working, you should get a good number for the large file sequential.

However, when you copy files in Windows, lots of smaller files will be way slower, and even with large files, you have no guarantee that the whole file is sequential (due to fragmentation) so it could still be slower.

800MB/s is still pretty good over USB. 600MB/s is on the slower side but not crazy slow either. I don't think anything is wrong.
 
cybereality said:
You'll never get the theoretical top speed when copying files in the OS.

Use CrystalDisk to check that everything is working, you should get a good number for the large file sequential.

However, when you copy files in Windows, lots of smaller files will be way slower, and even with large files, you have no guarantee that the whole file is sequential (due to fragmentation) so it could still be slower.

800MB/s is still pretty good over USB. 600MB/s is on the slower side but not crazy slow either. I don't think anything is wrong.
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Yes, yes, lots of small files still bad news in 2021, some new SSD controllers on the way to improve it any year now.
As I had said before, that is why I used a large 30-ish GB file and it's coming from a PCIe 4.0 SSD that should read at (but you'll never see) 7000-ish MB\s.
 
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