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Question

USB3 speed_theory vs.practice

May 22, 2015 7:07PM PDT

Data transfer speeds via USB port are very different. It certainly related on system settings (win7_64bit) as well as file type, USB2/3, etc.
My question is related to USB3 transfer, which should be the fastest, but sometimes it's frustratingly slow. I tried several new USB3 external hdds (WDpassport edge 500GB, Adata HV620_500), various flash memory. At the beginning of the big file transfer (1GB), it sets off in cca90MB/sec, then it slows down to 4KB/s. It's somehow improve? Update drivers, or something? I use both Windows Explorer or Total Commander, it's the same.
Thanks for your advice or tip for acceleration.
Peter

Discussion is locked

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Answer
So from what you said,
May 23, 2015 1:36AM PDT

I would say maybe the issue is not just "USB3", but some other bottleneck. Personally I have not use any usb3 so I can't say if that's normal but I have used sata vs usb2 and sata was definitely faster (my experience).

Just thinking out loud, maybe a new usb3 controller if you have the socket for it (I notice they are not that expensive).

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Answer
I find the slowest copy to be with Windows Explorer.
May 23, 2015 1:55AM PDT

For me, a command line copy is the fastest then after that RoadKil's Unstoppable Copier. I won't expand too much here but I think it's how it serializes the copy. USB of any version seems to like us copying one file at a time.
Bob

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The numbers you gave sound right. until that 4K
May 23, 2015 1:59AM PDT