Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uunet!convex!swarren
From: swarren@convex.com (Steve Warren)
Newsgroups: comp.sys.amiga.hardware
Subject: Re: 2.0 in FRANCES
Message-ID: <105878@convex.convex.com>
Date: 6 Sep 90 21:59:25 GMT
References: <444299@neabbs.UUCP>
Sender: usenet@convex.com
Organization: Convex Computer Corporation, Richardson, Tx.
Lines: 33

In article <444299@neabbs.UUCP> joost@neabbs.UUCP (JOOST BOERHOUT) writes:
>I can't explain why FRANCES needs the warming up except the darn thing
>is working on the edge of the (timing) specs. A heated chip will have
>a shift in the timing specs so this seems to be the case.

Yes, a common failure on higher-speed systems is the "cold" failure.
Some technicians debug a board like this with a can of freon:

1) Warm the board up and start a looping test that is known to fail cold.

2) Spray a chip with freon until it frosts over.

3) Let the chip warm up, then spray the next chip over.

4) Repeat until you find the chip that makes the board fail when it is cold.

5) Replace the chip.

6) Pray it is fixed.  ;^)

Note - freon cans used for this purpose use a spray nozzle with a metal
tube inserted in the nozzle to direct the spray.  The metal tube is grounded
through a wire so that the freon spray does not carry static charges through
the air, damaging the circuit.

A cold failure usually means there really is a problem with the board.  It
just happens that it is not noticeable most of the time.  That does not mean
you should not try to find the problem...
--
            _.
--Steve   ._||__      DISCLAIMER: All opinions are my own.
  Warren   v\ *|     ----------------------------------------------
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