Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wuarchive!zaphod.mps.ohio-state.edu!mips!apple!bionet!ucselx.sdsu.edu!polyslo!gaudi!csuf3b!jamespa
From: jamespa@csuf3b.CSUFresno.EDU (James Paul)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Leave it on?  Or once a week?
Message-ID: <1990Feb14.052956.4203@csuf3b.CSUFresno.EDU>
Date: 14 Feb 90 05:29:56 GMT
References: <77800007@m.cs.uiuc.edu> <9160@portia.Stanford.EDU>
Reply-To: jamespa@csuf3b.UUCP (James Paul)
Organization: C.Sci Dept., CA. State Univ, Fresno
Lines: 46

In article <9160@portia.Stanford.EDU> mmaston@portia.Stanford.EDU (Michael Maston) writes:
>...
>	It is good for any electronic device (including the Mac) to minimize
>the number of power cycles (turning it off/on) you put it thru.  Just as
>you might have noticed that light bulbs almost always burn out when you 
>turn them on, all such devices are put under a great deal of stress when
>voltage/current are applied to them suddenly.  If you leave them on all the 
>time, you (theoretically) should be extending their life expectancy.
>
>As for cost effectiveness, that is pretty much a function of the cost of
>electricity in your area.  If it is cheap, who cares?  If it isn't, well...
>Computers really don't gobble THAT much power.
>
>Mike
>Hardware/Software Engineer
>GTE Government Systems Corp.
>Mountain View, CA  94043

Well and fine, but remember that hard disks have a MTBF rating (mean time
between failure) and usually spin at about 3000 RPM. :-) If you don't mind
eating your disk drive's time away, no problem. Also, be sure to use a
screen saver. (Even though many CRTs have a limited life, it is fairly
long if treated with care.)

Seriously, with today's complex power supplies, (especially the one in the
mac SE/30!) it's ridiculous to leave one on for days to avoid a power cycle!

If you know you're not going to use the machine for the next couple hours,
power it down!

(As a side note, as system admin for NASA Ames/Dryden ATD, the first thing
I did was to change a small policy that required a group of local macs to
remain powered on all the time, except on weekends. _ALL_ their LaserView
monitors had been fried several times, and several machines had occasional
heatstroke during hot weather when the AC went off during non-working hours.
I told everyone to turn the things off when they went home, and there were
no further problems while I was there. :-) I'm no longer working at NASA,
though, and I hope they kept the policy.

I've said my piece. Best wishes,

-- 
--------------------------------------------------------------------------
UUCP:jamespa@csuf3b.CSUFresno.EDU                    Compuserve:72767,3436
GEnie:J.PAUL                                            Packet:N6SIW@K6RAU
AppleLink:D1231                                      America Online:JLPaul