Looking at the bandwidth touted by various connectors like USB 3, 3.1 or Thunderbolt 2 or 3 you would think they were meaningful but even the fastest NVME ssds are only getting something like 2000MB/s and most SSD's "regular" and my external SSD on a USB 3.0 connection gets something like 300MB/s. I know some allow more power and pass through options etc but in terms of speed of connection is there much point or real world difference between any of these? I have a four bay Thunderbolt 2 enclosure with hard drives connected with an adpater to my Thunderbolt3 port on my iMac and figure I might as well replace it with a USB 3 enclosure to free up a Thunderbolt port so I could toss on a T3 drive for my Final Cut Pro libraries. Seems to me I would not see any speed loss given the box holds hard drives and figure any USB enclosure would be equally fast given the hard drives are so slow and not limited by USB speed. Any problem with this thinking?
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USB or Thunderbolt Speed vs real world hard drive or ssd speed
- Thread starter santa
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I am having a little bit of a problem following your post and what you are asking...
I think you would, although it would not be a huge difference. USB 3 max transfer is 5,000Mbps, and SATA3 is 6,000Mbps, but accounting for overhead, there probably wouldn't be that much of an increase using a faster specification.
Using something faster like NVMe, I am sure you would notice a performance increase going from something like USB3.1 and TB1 to the faster TB2 and TB3.
For this question, you are asking if your four-bay enclosure that currently houses four HDDs and uses TB2 is switched to USB3, would you notice a difference in performance.
Maybe...
If you operate just one drive at a time, then you probably wouldn't notice a difference going to the slower USB3. Depending on the speeds of the HDDs, if you start using more than one drive, you may notice a difference. All four drives at the same time, unless the individual drives are really slow, I am sure you would see a performance decrease.
If the two or more of the drives are in some type of striping RAID, then you would most likely see a performance decrease.
I am unsure at what you are asking here. For example, are you asking if you put a SATA3 SSD on USB3, would you see any performance benefit of putting the same SATA3 SSD on USB3.1, TB1, 2, or 3?
I think you would, although it would not be a huge difference. USB 3 max transfer is 5,000Mbps, and SATA3 is 6,000Mbps, but accounting for overhead, there probably wouldn't be that much of an increase using a faster specification.
Using something faster like NVMe, I am sure you would notice a performance increase going from something like USB3.1 and TB1 to the faster TB2 and TB3.
For this question, you are asking if your four-bay enclosure that currently houses four HDDs and uses TB2 is switched to USB3, would you notice a difference in performance.
Maybe...
If you operate just one drive at a time, then you probably wouldn't notice a difference going to the slower USB3. Depending on the speeds of the HDDs, if you start using more than one drive, you may notice a difference. All four drives at the same time, unless the individual drives are really slow, I am sure you would see a performance decrease.
If the two or more of the drives are in some type of striping RAID, then you would most likely see a performance decrease.
Not sure if santa is asking about SSD or a RAID/multi-bay disk arrangement, but I have a similar question about TB3 real world performance. I have a 750+ GB photo library that’s currently on a USB 3 MyBook spinning disk attached to my iMac Pro, and the speed is horrendously slow.
I’m torn between external SSDs connected by either USB 3.1 gen 2 or TB3. The price difference is not insignificant, and I’m wondering if the real world performance advantages of TB3 are worth it.
I’m torn between external SSDs connected by either USB 3.1 gen 2 or TB3. The price difference is not insignificant, and I’m wondering if the real world performance advantages of TB3 are worth it.
I can add a few data points from my own experience. The cheap bus-powered USB disks, such as the WD MyPassport are pretty slow, around 100MB/sec. Older USB 2 hard drives top out around 35/MB sec. Larger desktop hard drives with their own power bricks typically give me around 180MB/sec. I have several Samsung T3 external USB 3 SSD's and they clock around 430MB/sec read and 400MB/sec write on my older computers (have not checked them on my new 2018 Mini yet).
Just got a 2tb Samsung T7 and it's a lot faster on my 2018 Mini via USB-C. Read is around 925MB/sec and write is about 840MB/sec. I have seen other posts that (IIRC) showed write speeds as high as 2000MB/sec and even faster read on thunderbolt 3. These are much more expensive and personally, I'm not doing anything that would justify the price difference.
Just got a 2tb Samsung T7 and it's a lot faster on my 2018 Mini via USB-C. Read is around 925MB/sec and write is about 840MB/sec. I have seen other posts that (IIRC) showed write speeds as high as 2000MB/sec and even faster read on thunderbolt 3. These are much more expensive and personally, I'm not doing anything that would justify the price difference.