Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!shadooby!samsung!aplcen!haven!adm!cmcl2!yale!cs.yale.edu!spolsky-joel@CS.YALE.EDU
From: spolsky-joel@CS.YALE.EDU (Joel Spolsky)
Newsgroups: comp.sys.ibm.pc
Subject: Re: POWER ON, POWER OFF...what's best?????
Summary: ON!!
Message-ID: <5865@cs.yale.edu>
Date: 17 Nov 89 05:55:47 GMT
References: <165@mscf.med.upenn.edu>
Sender: news@cs.yale.edu
Reply-To: spolsky-joel@CS.YALE.EDU (Joel Spolsky)
Organization: Yale University Computer Science Dept, New Haven CT  06520-2158
Lines: 21

In article <165@mscf.med.upenn.edu> ross@mscf.med.upenn.edu writes:
|
|The question is:  Is it best to leave this machine on constantly or is it
|  better to park the diskheads at the end of the workday and power the 
|  machine off.

This comes up all the time. The conclusion is that it is best to keep
the thing on because the strain on the circuits is greatest at
power-on, indeed, IBM internally rates PC's as having a mean time
between failures of n power-ups +/- 100% where n is some large number,
I think 10,000 for the original IBM/PC.  The idea is that MTBF is a
function of how often you turn the thing on/off.

You can park the heads at the end of the day if you want, and you
should blank the screen or switch that off to prevent etching.

+----------------+----------------------------------------------------------+
|  Joel Spolsky  | bitnet: spolsky@yalecs.bitnet     uucp: ...!yale!spolsky |
|                | internet: spolsky@cs.yale.edu     voicenet: 203-436-1538 |
+----------------+----------------------------------------------------------+
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