Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!unhd!news
From: pel@pan.ctron.com (Paul Leclerc)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: Re: Ringing CPU?
Message-ID: <1990Dec19.180651.13668@uunet!unhd>
Date: 19 Dec 90 18:06:51 GMT
References: <1990Nov5.210559.5733@maytag.waterloo.edu>
Organization: Cabletron Systems Inc.
Lines: 31

In article <1990Nov5.210559.5733@maytag.waterloo.edu> dmurdoch@watstat.waterloo.edu (Duncan Murdoch) writes:
>
>I've got a Northgate 486-25, and have noticed that under certain conditions,
>when it's in a loop asking for input I can hear a high pitched ringing

I have the very same condition on my old 286 clone with EGA and with
a monochrome monitor.  I notice it especially with the Emacs editor
called Epsilon.  Almost no other program does it.

>(maybe 8 KHz, but I'm not a very good judge of pitch).  For example,
>if I boot with almost no drivers or TSRs except Borland's TDH386.SYS (the
>driver for virtual debugging), I can hear the ringing when I'm at the 
>DOS prompt, and it becomes much louder after I've run the debugger and
>exited.  If I run a program, or just do a DIR, it stops until I'm back
>at the prompt again, so I think it must be that I'm hearing the CPU
>(or some associated circuit) resonating at the frequency of the input
>loop.

I think it may hav eto do with	the high intensity chars (ie real bright).

>Does anyone know whether this is a sign of an impending breakdown?  It 
>seems to me that the CPU (if that's what it really is that's vibrating)
>shouldn't vibrate enough to emit sounds, and if it does, is likely to
>work itself loose from the socket.

Ieeee!!!  I hope not.  I don't need another computer breaking down
right now.


Paul L.
pel@ctron.com