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Well, This is not the answer, but a recommendation, I also had issues with a external HDD that I bought for Back up purposes. I found that USB transfers were slow at best, & ( No matter the OS or machine, as I tried it on several ,3 ) It was not the HDD either, I guess it was the interface controller,in the enclosure. Well how did you figure this out , you ask. Answer = the box I purchased came with only USB cables, & the power cord ( outlet type adaptor ). The box had other ports, firewire, ( which I Did Not Try ) & E-Sata. I went to the Local retail store & purchased an E-Sata connector Cable. Transfer speeds were simply amazing, almost like writing to the internal drive ( it still takes about 30 sec for the OS to recognise the drive , probably due to the size 1.5TB ) but after that all is fine. I think I was not getting the full benefit from the USB interface. I haven't switched back to the USB again.
So if you can get a cheap enclosure that will support E-Sata , that is what I recommend.
I hope this gives you some ideas, Have A Good Day.
" Do Not Do Wrong Twice,That Which You Could Have Done Right The First Time
Main = HP Pavilion DV4-1275mx - OS=Mint_CE x64KDE/LXDE,& x64Kubuntu