[comp.sys.mac.hardware] Multifinder Makes my SE/30 Whine

rc3h+@andrew.cmu.edu (Ross Ward Comer) (02/14/90)

Yes, whine.  As in a high pitched noise.  Audible just enough to be
annoying.

Symptoms:
Occurs only under Multifinder, not finder.
Occurs on a new SE/30 (with Apple's hard-drive 'fix' (ha-ha))
Occurs only when >1 Meg RAM installed
     (ie doesn't happen with 1 Meg, does with 2M, 4M, 5M, etc)
Occurs whenever system is idle (waiting for user input)
Stops whenever their is much system activity
     (ie heavy computations/programs running)
Stops on any user input (ie holding the mouse button down stops it)


My thoughts:
Power supply.  Heavy computations or user input (downclick) increase
power demand which increases frequency to inaudible or
non-vibrational.

I don't think it's the 40M hard drive.  Downclicks and heavy (internal
memory) computations wouldn't change anything with the drive.

What stumps me is that it only happens under Multifinder and not
Finder, and it only occurs when >1Meg RAM installed (stopping on
downclicks is a little funny too in my opinion).

Any suggestions/thoughts would be much appreciated.

ross
rc3h@andrew.cmu.edu
Carnegie Mellon University

jasper@ux1.cso.uiuc.edu (02/16/90)

   If you're talking about a very high pitch like that of a monitor left on
when the computer is turned off (alot of people I know can't here that but it
bugs the hell out of me), then my SE/30 does it sometimes too.  It seems to 
be very directional (or maybe that's because it's so faint)  I did notice that
pulling down a menu makes it go away sometimes.  Yes it's only at idle time
like you said.  I haven't checked whether it's particular about multifinder or
not.
  My guess is that it is some kind of monitor noise because that's what it 
reminds me of.  I think it occurs when the screen is idle, ie. it doesn't seem
to do it when the screen saver (Moire) is drawing on the screen.  If you
ever figure it out, let me know.  Maybe having a little window to the side with
a constantly changing shape in it (force the screen to always draw something 
new) would make it go away.

Nick Jasper
jasper@ux1.cso.uiuc.edu
University of Illinois