I picked up another external usb/sata hard drive since the first one
seems to be so useful. This time, it's an enclosed 2.5" drive instead
of the 3.5" docked drive. In case anyone is thinking about an
external drive and wants to avoid risk, here's what I got...
The drive:
Western Digital Scorpio Blue WD2500BEVT 250GB 5400 RPM 8MB Cache 2.5" SATA 3.0Gb/s
http://www.newegg.com/Product/Product.aspx?Item=N82E16822136387
The enclosure:
Rosewill RX81U-AT-25A Rigid aluminum 2.5" SATA to USB 2.0 Ext. Enclosure
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182138
Total cost was just under $60 with shipping, a bit higher than the
"combo" drives but this way I know which drive I'm getting :-)
Tested (lightly) on x86-64, trimslice, panda, and olpc - they all
worked just fine with a single USB A plugged in, although the provided
cable was a Y cable in case you needed more power (i.e. two USB A
plugged in).
The x86-64 showed an easily sustainable 37 MB/s streaming read, which
I think is the USB2 upper limit. The trimslice showed a sustained 25
MB/s, panda 23-25 MB/s (that internal hub is shared with ethernet) and
the OLPC 10-25 MB/s (not sure what else it was doing). They all
peaked at 25 MB/s which is the most I've ever seen an ARM board do.
The OLPC even mounted it automatically (I had fdisk'd it earlier).
The drive is a snug fit in the enclosure - no internal screws to hold
it in place, but the case required a slight squeeze to close, so there
must be something flexible in there pressing the drive into the
connector. No rattles.
The enclosure has a separate DC power jack but does not come with a
wall wart. The USB chip does tell the host that it's self powered,
though, which is obviously a lie when you only have the USB plugged
in.