Xref: utzoo comp.sys.3b1:97 comp.sys.att:11694
Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!lll-winken!uunet!bywater!scifi!hybrid!mdapoz
From: mdapoz@hybrid.uucp (Mark Dapoz)
Newsgroups: comp.sys.3b1,comp.sys.att
Subject: 3b1 memory problems
Message-ID: <1991Feb5.070902.1260@hybrid.UUCP>
Date: 5 Feb 91 07:09:02 GMT
Sender: mdapoz@hybrid.UUCP (Mark Dapoz)
Organization: The Home for Unemployed Basselopes, Toronto, Ontario, Canada
Lines: 27

Well, I knew it was bound to happen sooner or later, unfortunatly it was
sooner than I had hoped.  It seems my trusty 'ole 3b1 has packed it in, it
now just sits there with the number 1 & 3 led's on when I turn it on.
Looking in the hardware tech ref this indicates that test 5, the dynamic
ram test is failing.  Great, one, if not more of my 72 ram chips has died.
I already have 2 meg on the motherboard so I don't want to go ripping them
all out just to find out which one is bad.  Does anyone have any idea how
I can go about narrowing down exactly which ram chip is bad?  I can't even
boot a diag disk so none of those fancy tests will do me any good.  I
remember some talk recently about making up some new diag roms to help
track problems like this down.  Did anyone ever get this working?

It's really bizzare how the machine just gave out for no apparent reason.
There I was, working on my Sun while the 3b1 was madly unpacking a few meg
of news, and then...... silence.  I figured the kernel just hung for some
bizzare reason so I reset the machine.  It cleared the screen as usual and
then it went to alternating black and white lines,  uh oh.  I quickly reset
it again... same thing.  Powered it down completely... same thing.  Luckily
I have a second 3b1 for times just like this.  I even added the second drive
expansion socket to it just in case I had to swap boards.  After opening up
both machines and swapping boards I now have my main machine back up and
running but the spare one is now dead.  Any suggestions on how to fix this
dead board would be greatly appreciated.
-- 
Managing a software development team 	|   Mark Dapoz  
is a lot like being on the psychiatric	|   mdapoz%hybrid@cs.toronto.edu
ward.  -Mitch Kapor, San Jose Mercury	|   mdapoz@torvm3.iinus1.ibm.com