On 12/13/2011 07:48 PM, Charles Curley wrote: > > Most hard drives for the last 15+ years have had provisions for > graceful shutdown in the event of abrupt power failure. But I prefer > something I can test. > > I've had too many problems with the external power supplies or their > connectors failing to want to continue with those. >
The size and power constraints you list likely limit your options to 2.5" drives. I favor constructing my own external drives because that way I can select the drive I want and a snappy enclosure. If you shop the deals the cost is about the same either way. Power-wise, the 1tb units I looked at range from .6A-.85A, so in order to achieve 100% bus powered, you'll need to use 2 USB 2.0 ports to ensure there is enough power (the enclosure I bought came with a dongle cord that had a second port with only the power pins connected). A powered USB hub might also be an option for getting extra power but not using the second port. That takes us back to the external power supply part again though. The USB spec for 2.0 says .5A max power per port. USB 3.0 increases this to .9A per port. People I know have had luck running a .6A drive off of a single USB 2.0 port. Whether this means the port is pulling more power or the drive is getting less, I cannot say. I haven't tried it myself, and for the sake of hardware health, I don't think I will. My favorite part of building my own drive solution is I get to pick the drive in the end. This lets me pick from a wider range of brands and models than I would have access to by purchasing a specialized external drive. HTH --Henry /* PLUG: http://plug.org, #utah on irc.freenode.net Unsubscribe: http://plug.org/mailman/options/plug Don't fear the penguin. */
