[SOLVED] How to determine whether USB 3.0 is being used.

273 · 12-16-2012, 07:18 AM

I have a USB 3.0 external drive plugged into the USB 3.0 port of my PC. However, since both are backwards compatible with USB 2.0 how do I know whether they're running as USB 3.0 or not?
I'm running Debian Sid with a Gigabyte GA-990XA-UD3 motherboard if that matters, though I'd prefer a non distro-specific solution.

TobiSGD · 12-16-2012, 08:13 AM

Just copy a large file to the device and watch the transfer speed.

273 · 12-16-2012, 08:34 AM

I just tried with mc and it showed 110MB/s, does that mean it's only running as USB 2.0? Disk Utility tells me it's connected at 750MB/s.
Is there no way to determine other than checking the speed?

TobiSGD · 12-16-2012, 08:37 AM

USB 2.0 is limited to 480MBit/s, which in reality comes up to 30-35 MB/s maximum. So if you get 110MB/s USB 3.0 clearly is used.

273 · 12-16-2012, 08:41 AM

Thanks, seems obvious when you put it like that.

Edit: I'll leave this as unsolved for a little while though as I'd be interested in how to determine which driver was being used by querying the system also, for future use.

DavidMcCann · 12-16-2012, 11:52 AM

I think the command
lsusb -v | grep bcdUSB
should tell you what you need to know.

273 · 12-16-2012, 12:19 PM

Thanks, "lsusb -v" does, indeed, give the USB versions.