USB3 speed theory vs.practice

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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

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Yeah, I’ve yet to reach anywhere near USB 3.0 “advertised” speeds. That is even with mechanical & or SSD drive on
a brand spanking new X99 chipset. It still seems slow to me, although I havn’t actually clocked it, I’m certain it’s more than 90, but varies sporadically throughout the transfer.

*You could try a USB chipset update if your board is up for one. Chipset updates should always be performed
when a new one comes out. If you’ve got an older board, say early USB 3.0 adaptation, you’ll likely not see one.
*Perform a fresh boot before attempting to transfer large files, just to clear out the memory.
*Take note of other processes on the system that may be using memory the same time your about to make
a file transfer with USB 3.0 and close them.
*getting into the practice of keeping a clean and lean system will usually boad well for USB transfer speeds too.

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It ain’t pretty. It never is. I remember a discussion about this including input from the USB Stds. Committee (whatever they are called). If I find it I will post the link. Based on prior speed claims for various I/O ports you get what you actually get and over a couple of years you get twice the original speed via various tweaks from various sources. But if it is 10% of what the spec authors claim at the beginning it is doing well.

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I’ve seen the same thing. In general:

– Some USB 3 devices fail to be recognized by USB 3 ports. The USB device cannot be used until the computer attaches it correctly;
– I’ve had very good luck with those same USB 3 devices in USB 2 ports. The device then works fine though at slower speed of course. Windows then taunts you with messages that “this device could work faster” messages,
– A few very large files transfer much, much faster than thousands of very small files. The difference is dramatic, on the order of 10X – 100X speed difference.

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Here is the link I remembered that I thought might apply to this discussion:
http://www.tomshardware.com/reviews/usb-3-uas-turbo,3215.html

It does not since it is really for attached (external) mass storage drives.

Here are a few more that I explored for explanation (found in history):
http://event.asus.com/mb/2010/The_Best_USB3_Experience/The_UASP_For_USB3.0.htm

https://en.wikipedia.org/wiki/USB_3.0#Data_transfer_and_synchronization

http://vr-zone.com/articles/usb-3-0-speed-tests-7-way-host-controllers-roundup/13358.html

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