I've already bought a replacement drive but I was wondering on whether or not to hold off on replacing the "failing" drive until RAID says it's actually degraded. Although the drive fails the hardware diagnostics, the Intel Storage Manager still indicates that the RAIL1 volume status is OK. Is it possible the hardware diagnostics give false positives?
Also, I can't figure out an easy way of identifying the physical disk that corresponds to "Drive 2 -- Fail. Return code 7". I suppose I could unplug one disk and rerun hardware diagnostics, but I'm guessing that that would "break" the RAID array.