Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!pt.cs.cmu.edu!b.gp.cs.cmu.edu!Ralf.Brown@B.GP.CS.CMU.EDU
From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.sys.ibm.pc
Subject: Re: COBOL, power cycles, and hard disks
Message-ID: <2540580f@ralf>
Date: 21 Oct 89 11:50:39 GMT
Sender: ralf@b.gp.cs.cmu.edu
Organization: Carnegie Mellon University School of Computer Science
Lines: 23
In-Reply-To: <4005@cbnewsc.ATT.COM>

In article <4005@cbnewsc.ATT.COM>, olaf@cbnewsc.ATT.COM (olaf.henjum) wrote:
 >(3) I've gotten conflicting information on the necessity of manually parking
 >    the hard disk heads before powering down the machine.  Some
 >    people have told me that one should ALWAYS do this for ANY kind
 >    of PC or PC-clone.  Others have said that this is necessary only
 >    for the PC/XT due to a design flaw in the first XTs that came out,
 >    and that AT machines automatically park the heads correctly whenever
 >    they're powered down (i.e. there's no need to manually run some utility

It's not the computer, it's the drive.  If you have an autoparking drive
(goes "clunk" when the power is shut off), then you don't need to
manually park the drive.  Most XT drives need to be manually parked,
most AT drives are autopark (I think the split is stepper motors need
manual parking, voice coils park themselves).  I normally park my
autopark drive anyway, so it doesn't hit the endstop as hard when the
power is shut off.
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"How to Prove It" by Dana Angluin
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