I saw a pretty good deal today on an internal 500gb WD "green drive" (http://www.wdc.com/en/products/greenpower/index.asp?language=en) which is supposed to keep power usage low.

I think that should help overcome the Airport Extreme's tendency to keep drives constantly spinning, but I was wondering if anybody had any experience using them in an external enclosure connected to an AE.

Even if you don't have firsthand experience I'd love your thoughts.

Cheers,
Ari

I think that should help overcome the Airport Extreme's tendency to keep drives constantly spinning

Probably not.

My only thought, Ari, is that an external drive continually spinning--and/or sleeping, waking, spinning down reliably--has less to do, if not nothing to do, with the particular drive itself and much more to do with the interface/chip/bridge of the enclosure. So by all means jump on a good deal for a good bare drive that gets good marks for running cool or running quietly, that in itself is a good thing, just realize it's the enclosure, and its hardware and firmware which will make the difference.

I don't have a USB external connected to an Airport Extreme so I'm of no specific help to you. I do have a Seagate Freeagent Pro connected to an Intel Mac over USB which does wake and spin down just fine--which is rare in terms of Macs and USB.

I just did a quick check of two other externals over USB that I have around the house:

a WD MyBook "Home" edition (FW, USB & eSATA)
a LaCie d2 extreme (FW400, FW800 and USB)

and was pleasantly surprised to find both spin down, sleep and wake just fine, when connected to Intel or PPC Macs over USB. (I've always had these connected via FW400 or FW800, so I never knew how they'd do over USB.) Sometimes these enclosures have one chipset for firewire, and a different one for USB--so it's possible an enclosure with an Oxford for firewire will not spin down when connected via its cheaper USB bridge.

Again, sorry, no direct experience with an AEBS. You might shoot an e-mail off to OWC--they'd know by now if any of their external storage options spin down when attached to a basestation USB.

This is a great help, thanks. I have an enclosure with an Oxford 924 bridge, so I'll poke around, check the xlr8yourmac.com forums and report back.

I briefly had a Segate branded external drive that spinned constantly. Complained to CC and they exchanged it for a WD. The WD branded external (previous gen, not the book) spins down when USB connected to a mac or an airport extreme. Don't know if spinning down is 'better' but I much prefer it.

Apple just released yesterday software update that officially provides for Time Machine to USB connected drives. You might want to try this first to see if it resolves your usb spin down issue:
http://www.appleinsider.com/articles/08/03/20/update_enables_time_machine_backups_to_airport_extreme_usb_d rives.html

ken