Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!wuarchive!brutus.cs.uiuc.edu!apple!hardie
From: hardie@Apple.COM (Robert H. Tankersley)
Newsgroups: comp.sys.mac
Subject: Re: Quantum ROM fix report
Summary: Not an official statement
Keywords: quantum
Message-ID: <37039@apple.Apple.COM>
Date: 6 Dec 89 16:09:01 GMT
References: <14618@well.UUCP> <9323@batcomputer.tn.cornell.edu> <20837@mimsy.umd.edu> <27801@dhw68k.cts.com> <32331@auc.UUCP> <89334.141000ALE101@PSUVM.BITNET> <17524@netnews.upenn.edu> <24638@cup.portal.com>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 26


I am not authorized to make any statements for Apple.  But I work for them
and might be able to shed some light.

From what I understand the PROM fix is intelligent.  When it performs the
random seeks it monitors the resistance it encounters and adjusts force
accordingly.  Therefore as the lubricant smooths out random activity will
decrease over time.  When your dealer replaces the PROMs he is supposed
to run a diagnostic that excersizes the drive and smooths out the lubricant.
If this step is skipped the drive will sense more resistance and seek more
until it is happy about the viscosity of the lubricant.  This could explain 
increased activity for a short period of time.

I also understand that tests have been performed that show that the new PROMs
do not result in a performance change nor do they affect durability.

This is what I have heard from Apple.  But I have not been involved in any
testing or development of the fix.  I'm just a simple field person.

Hardie Tankersley                        hardie@apple.com
Assosciate Systems Engineer
Apple

Atlanta

Again: The above statements are not Apple's, they're mine.