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From: ollef@osiris.sics.se (Olle Furberg)
Newsgroups: comp.sys.mac
Subject: Seagate drive self-seeking -- what is the truth?
Summary: What about Seagate drives?
Keywords: Quantum, Seagate
Message-ID: <2676@osiris.sics.se>
Date: 14 May 89 01:34:46 GMT
References: <4267@ucdavis.ucdavis.edu> <102@mountn.dec.com>
Reply-To: ollef@sics.se (Olle Furberg)
Organization: Swedish Institute of Computer Science, Kista
Lines: 29
Was: "Quantum drive self-seeking -- the truth"


In article <102@mountn.dec.com> minow%thundr.dec@decwrl.dec.com (Martin Minow) writes:
>Summary: people notice that their 3.5 inch Quantum (40/80 Mbyte)
>disks occassionally do some I/O without any prompting from the
>host.  They asked why. I talked with my local Quantum technical
>support person.  Here's his answer:
> [---]
>Quantum drives contain a thermistor that triggers recalibration when
>the temperature changes by 2 degrees-Celsius.  Recalibration is also
> [---]

 I have an Apple HD40 with a Seagate 3.5 inch drive (Seagate ST-157N).
It behaves in the same way, I/O every 20 minutes. It's a bit irritating
because I have the HD under my bed. However, if I park the heads the
seeking stops.
 Note: It's in the HD, because:

1. It does not depend on MultiFinder or any exotic inits:
   I've tried the good old System 3.2 without any inits: it's still there.

2. It continues even if I turn off the Mac

Does Martin's explanation also apply to Seagate drives?


           /Olle


PS. Driver software: Apple's  HD SC Installer version 2.0