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From: boyne@hplvli.HP.COM (Art Boyne)
Newsgroups: comp.sys.ibm.pc
Subject: Re: Why do magazine's review mail-order PC brands
Message-ID: <360028@hplvli.HP.COM>
Date: 16 Mar 90 17:49:21 GMT
References: <1990Mar6.024915.1295@cs.dal.ca>
Organization: Loveland Inst. Div
Lines: 34

karl@ddsw1.MCS.COM (Karl Denninger) writes:

>>Response 10 of 11 (9561) by dlow at hpspcoi.HP.COM on Wed 14 Mar 90 03:32
>>[Danny Low]
>>
>>We are not too happy about this problem either. If you are replacing
>>stiction problem drives you are doing your customers a disservice.
>>This problem
>>is inherent in the design of the drive according to a Seagate engineer
>>I talked to.

>Given enough time,
>it WILL stick again.  Once these drives show this symptom, the only permanent 
>fix is replacement.

Sorry, Danny, but Karl is correct according to information I received from
engineers at HP's Greeley Division, which used to deal with Seagate drives.
However, Karl's description of the problem, while basically correct, is
not perfect.  The problem in the past (eg., ST4051) has been with the seals
between the spindle motor and the sealed media compartment.  The lubricant
*outgasses* through the seals, leaving a sticky residue on the inner tracks,
which are indeed the "park" area.  This is a long-term cummulative problem,
and when enough residue has collected, the heads begin to stick and, while
the "twist" will free them early on, eventually enough residue accumulates
that you will tear the heads off the actuator trying to free them.
Replacement *is* the only long-term solution.

The Greeley Division engineers also told me that, while some drives will fail
and others not, those destined to fail start showing symptoms *very quickly*.
A drive that has no symptom after ~6 months are unlikely to ever fail.
(Witness the ST4051 that I have, manufactured during the height of their
problems, now 5 years old and going strong.)

Art Boyne, boyne@hplvla.hp.com