Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!veritas!amdcad!sun!aeras!rob
From: rob@aeras.uucp (Rob Rogers)
Newsgroups: comp.sys.mac.hardware
Subject: Re: Weird Mac II hardware problems
Summary: Check Your power
Keywords: Mac II, Power, crash
Message-ID: <1991May21.182304.26360@aeras.uucp>
Date: 21 May 91 18:23:04 GMT
References: <1991May14.184059.22557@batcomputer.tn.cornell.edu>
Reply-To: rob@aeras.UUCP (Rob Rogers)
Followup-To: comp.sys.man.hardware
Distribution: usa
Organization: Arix Corporation, San Jose, CA.
Lines: 56

In article <1991May14.184059.22557@batcomputer.tn.cornell.edu> rasio@theory.tn.cornell.edu (Frederic A. Rasio) writes:

>I am having a very weird hardware problem with a Mac II.
[stuff deleted about strange crashes with no pattern].......
>
>Three times I've brought this Mac to an authorized Apple dealer 
>for inspection (a different person each time) and they found 
>absolutely nothing wrong with it. The third time was last 
>week, and this time I told the technician -- after 
>he'd run the usual diagnostic software and found nothing again -- to 
>just let the Mac run all the time and wait for a crash. It's now been 
>almost a week and still nothing...
>It seems that the problem magically disappears whenever I move the
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>Mac away from home. However, I don't see what could be wrong
^^^^^^^^^^^^^^^^^^^^
>with its usual environment: it's in a relatively cool room, with 
>little dust, no direct sunlight, etc... 
>
>Current system configuration: Mac II (3 yrs old), 8 Megs, system 6.0.7, 
								  ^^^^^
>					Fred Rasio
>					rasio@astrosun.tn.cornell.edu


You problem is exactaly what happened to me with my Mac II.
	Check Your Power !!!
Check your house wiring. 
Not just voltage, but spikes, too (you can rent the machine that 
does that from big rental places).  
If that's the problem, tell P.G.&E (or whoever does your utility power). 
It can be a pain to get them to believe "they could do anything wrong", 
but it happens.

Very often, you will have somebody in your neighborhood with a 
5000watt arc-welder, or something like that. 
Every time it gets turned off (yes, off) -- zapp goes the mac.
That's why there's no pattern.
The embarrassing thing is when it's your wife's hair dryer :-)
(no, that wasn't me)

The utility company is required by law to give you "decent" power.
It's what you pay them for.
If the spikes are that strong, something big is going on.

By the way, if you don't need it specifially, your Mac II will be 
much happier with system 6.0.5. That's not your problem here, though.


Good luck
Rob
-- 
	Rob Rogers
	Art Director, ARIX Computer Corporation
	{mips|sun|wyse|jade}!aeras!rob <> rob@aeras.UUCP <>
	73377.1017@compuserve.com <> GEnie=R.ROGERS10 <> AOL=MacGun