I thought the point about which version chassis the drives in to be a valid point. I believe the backblaze design has 1 pound drive vibrating at 120hz or so su

I thought the point about which version chassis the drives in to be a valid point. I believe the backblaze design has 1 pound drive vibrating at 120hz or so supported by a SATA connector. I don't know the SATA specification, but I suspect they aren't designed to support the drives weight. If SATA connectors where designed to support the drive they wouldn't be plastic. Additionally the SATA Multiplier boards (thin fiberglass with delicate traces) are supporting the weight of 5 drives each. This would also explain why the enterprise drives (typically heavier, more platters, and with a more conservative design) are less reliable then the consumer (with typically higher density platters).