MegaSack DRAW - This year's winner is user - rgwb
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80 hour estimate to copy 300 Gb of data from one USB HDD to another. Sounds rather a lot. Is that normal?
Errr... You've probably got them plugged in via a USB1 connection, not USB2. USB1 runs at a fraction the speed of USB2, 300GB via USB2 should only be a few hours tops.
only an estimate based on current data transfer rate. mileage may vary...as may date transfer rates! are they both usb 2.0? oops too slow on the keys for me!
how do you tell if a slot is usb1 or usb2? isn't it the same plug?
EDIT Ah! looks like the donor drive has a transfer rate of 12mb/s where as the destination one is on 480 mb/s.
yes, but one (or all) will be allocated as usb 2.0 by the usb hub. you could try them all to see if the tx rate improves?
[url= http://www.usbman.com/Guides/checking_for_usb_2.htm ]clicky[/url]
will do...thanks
I've tried the slow device in the 'usb2' port and it's still runs at only 12mb/s. It's an old external HDD (4 years or so) - can the device be usb1 and not transfer at the fast rate irrespective of where you plug it in?
thanks for the link tumnurkoz, but I'm using Linux.
That's exactly it - the limiting factor is your slower usb1 (actually usb1.1) drive/interface. Yes, the larger slot-style plugs are the same for both (there's a mini connector for things like phones/cameras etc)
You'll always get something distinctly less than the raw usb speed.
Eg the 480 Mbps figure (60 Mbytes/s) is the base signalling rate, *not* the effective data rate, and doesn't include a whole lot of overhead in the usb protocol (ie how the signalling works). The maximum rate you'd get in practice would be about 52 Mbytes/sec, in reality with a recent PC it might achieve 32-45. If the disk drives keep up of course 🙂
Should you care 😉 - a usb2.0 host (generally a pc) has to support High speed (480MBps), Full Speed (12MBps), and Low Speed (a whacking 1.5Mbps) 'cos any of that lot may be connected to it - your usb1.1 device will run at 12Mbps peak. A keyboard or mouse would probably be Low speed.
I suspect you've got a usb2.0 hub, but if you were using an old one that was usb1.1 a similar thing would apply - except now a usb2 drive connected to the pc via that hub would just work at 12Mbps, since the hub would be the limiting factor.