Hello, I would think that with a USB 3.0 hub, all data transfers would be going through the one USB 3.0 port on the X220, whereas with an ExpressCard adapter, it would be going from USB 3.0 port to another.
On desktops, I know it is much faster to directly attach USB 2.0 hard disk drives via their own USB ports directly to the motherboard or via a PCI card than it is to place them on a shared hub. I would imagine it is the same with USB 2.0. Aside from using an ExpressCard, another possible option might be to connect the X220 to an ThinkPad Mini Dock Plus Series 3 (FRU 4338-10U, I believe), which has an eSATA port, and hook up one of the other external drives to that, assuming it has an eSATA interface, as well. You may have to do some benchmarking, though, to determine which interface is fastest for read-intensive and write-intensive operations. It could be that it is better to put the source or the target disk on one interface versus another. Regards, Aryeh Goretsky At 10:00 AM 12/28/2012, you wrote:
Message: 1 Date: Thu, 27 Dec 2012 17:04:40 -0500 From: Andrew Webber <[email protected]> Subject: [Thinkpad] X220: USB 3.0: Hub or ExpressCard? To: ThinkPad List <[email protected]> Message-ID: <[email protected]> Content-Type: text/plain; charset=iso-8859-15 I have an X220 with one USB 3.0 port. So far all the USB 3.0 devices I have are external HDs. Two are self-powered and one is USB powered. Any one of them is great when hooked up to the USB 3.0 port, but transferring files between drives is very slow (USB 2.0 speed of course). I expect to get another self-powered 3.5" drive in the next few weeks. Looking on Amazon.com, I see I essentially have a choice of a 4-port USB 3.0 hub, or a 2-port ExpressCard 34/54 card. The former will result in four USB 3.0 ports, the latter in three. The card also takes up less room in my kit. From the reviews, it seems none of these devices will give the full (4.8?) speed of USB 3.0, but that it may not matter as long as I'm hooking up rotating hard drives. Also the ExpressCard at least doesn't give enough power to power the small HD, but for now I can use the built-in port for that drive. In terms of cheap, not surprisingly everything has some negative reviews, but surprisingly some have pretty high ratings. I'm seeing a 4-port hub w/2A adapter for U$30 shipped (ASIN B005QWY3PU, 4/5*). The related 7-port hub is U$50 shipped. Of the cheaper hubs, ASIN B007BWTOHU (U$27) seems to have the best ratings. For ExpressCard, ASIN B004YB60KA (54mm) is U$6.45 shipped and some negative reviews. Same for ASIN B0046XUMDW (54mm) U$10.76 shipped, rated 3.5/5*. There's a bunch in the $10 range. If I get smart and limit to 4* and better (and Prime), cheapest ExpressCard adapter is ASIN B006K25AX4 at $29. Cheapest 4*/Prime hub is ASIN B004WM36WG at $26. My question really, is first if anyone has experience with any of these (or another in the <$30 range), and secondly if there are significant reasons I should go with ExpressCard vs. Hub and why. Thanks! - - Andrew mailto:[email protected]
_______________________________________________ Thinkpad mailing list [email protected] http://stderr.org/cgi-bin/mailman/listinfo/thinkpad
