On January 22, 2004 9:57 PM, Konrad Strauss wrote:

> Of course these drives were spinning and subject to stress which caused
> their failure. If the drives were in storage they would not have been
> subjected to stress.

On the AES/ ISO Joint Technical Commission on Magnetic Media Stability, we
have recently been talking to the manufacturers of HDD's.  From what we have
been able to learn, all longevity/stability testing that has been done has
been while the drives were spinning.  The manufacturers have not done any
testing and have no collected data on the what happens to the drives if they
are inactive and sitting on a shelf.

One might keep in mind the published papers on magnetic tape where the
manufacturers produced testing that "proved" some tapes could survive
thousands of passes before showing significant degradation in signal
reproduction. Of course, this testing occurred in controlled laboratory
conditions and the tapes were simply shuttled back and forth on a single
carefully aligned and maintained machine.  The tests implied longevity for
the tapes but it doesn't work this way in the real world.

I would be hesitant to assume that HDD's are safe to store for long periods
on the shelf without some significant testing of HDD's that have been
exposed to various conditions while not in the spin mode.

Peter Brothers
(201) 440-6589

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