USB 3.0- enough power..?

John Fridinger

macrumors newbie
Original poster
Jul 25, 2012
In a 2012 cMBP that is on its way I'm going to be replacing the 750/7200 HD with a Samsung 830, and putting the HD into a USB 3.0 Sata 3 external enclosure for back up... Does USB 3.0 provide enough power to the HD, or is an enclosure with additional power necessary..? And if so, such as..?

And a connected question, if hooked to a USB 2.0 connection on another machine, enough power there...?

Many thanks for all the great info in these threads...


macrumors 68020
Feb 8, 2008
A 2.5" drive can usually be powered over the bus (especially on Macs). I don't see very many externally powered 2.5" enclosures anyways.


macrumors 68040
Jun 27, 2009
USB 3.0 should be able to provide enough juice to pretty much all 2.5" drives since it can supply a decent bit ore current than USB 2.0.

The enclosure should work in a USB2.0 port, but you *may* need one of those 2-ended USB cables to get extra juice from a second port.