To flog the old horse one more time, let me add that I read a MTBF of 150 years as meaning that if my computer center has 75 hard drives of that type spinning away, I can expect an average of one drive failure (of the kind measured by the MTBF number) every two years. In this example, other vendor MTBF figures will differ, and would result in different drive replacement expectations, and different cost projections. Jon On Sat, 18 Feb 2006 18:21:34 -0600, nk <netkat at comcast.net> wrote: > > so much for 150 years, eh? > > ;-) > > nk