I think I've got it. Instead of thinking about it in abstract terms, it helped to actually engage ye old brain and think about the possibilities: (1) That I know of, Apple has used WD, Seagate, Hitachi, Toshiba, and Samsung for their drives. (2) Of these, I've seen WD, Seagate, and Hitcahi in the XServe & XServe RAID. (3) WD RE3's are used in the '09 1TB ADM's, maybe not exclusively. There's an '09 XServe that was delivered to my work a few weeks ago and that's what was used in it. (4) My '08 came with 3 1TB Hitachi HD72101KLA330's as mentioned above. (5) After looking at each of the possible vendors' enterprise-level drives (even though the ones used in mine are technically desktop-level, which is kind of surprising to me), I did a few searches based on the model numbers of the drives that Apple would probably use, Hitachi's 2TB SATA 3Gb/s in particular (HUA722020ALA330), and I found a link to a Google Groups thread that kind of confirms it: (5.1) http://groups.google.com/group/macenterp... Tada,...