david@wiley.UUCP (David Hull) (11/16/87)
I posted last week asking for advice about a quiet replacement fan for
my Macintosh SE, and specifically the SEaBREEZE fan that ComputerWare
carries. This article is a summary of the responses I received.
SUMMARY
You can replace the fan in a Macintosh SE that is significantly quieter
than the standard one for about $15 (the price of the fan). Or for
$40 dollars you can buy a kit from ComputerWare which contains the
fan, some double sided tape, cable ties, and instructions.
This modification is not for the faint of heart. You will have to
remove the old fan and solder in power for the new one. Needless to
say, doing this will void your warranty.
INTRODUCTION
I received three replies from people who have actually installed a
replacement fan. Mike Farmwald bought a fan from an electronics parts
store and installed it himself. Mike Parker and Patrick Mead each
bought a fan from ComputerWare (but I'm not sure if this is the same
fan they are selling now).
I have read articles which give instructions on how to replace a resistor
on the analog board to slow the standard fan down. I did not consider
this upgrade because it reduces the air flow produced by the fan.
THE FAN
You want a 12V DC fan that is about 2.25 inches square and draws
about .1A. The Apple fan moves about 10 CFM of air, so you want a fan
that moves at least that much. The ComputerWare fan moves about 23 CFM
(lots more!).
INSTALLATION
For those of you who want to buy and install your own fan, here are
Pat Mead's instructions:
The parts in the ComputerWare kit are a toyo fan 12V 0.1 amp, two
strips of double stick tape, and a heavy nylon tie 12in or so long
(Radio Shack has them). I used a flex screwdriver with the socket
head on to get to the old fan bolts. Hold the other side's screws
with a screwdriver and undo the nuts. Don't try to unscrew it. I
tried it and striped the screw (what fun). Cut the black wire to
the old fan (I did it near the silicon blob). Next unsolder the
yellow wire. Mount the new fan with the double stick tape (make
sure it blows out) and the nylon tie. The nylon tie goes around the
fan and through the old screw holes to tie it to the circut board.
Now solder the red lead in the hole you took the old fan's yellow
lead from (that's 12V straight from the power supply) and screw the
black to the chassis ground screw. That's it! Don't try this
unless you know how to solder and are willing to take chances
working on your own Mac. Also it will void your warranty. Use
this info at your own risk (I can't be responsible for anyone's
hardware skills).
CONCLUSION
I will definitely be replacing the fan in my SE.
I'm going to order the fan from ComputerWare, because I'm lazy and
don't feel like shopping for my own fan. I don't know if the standard
SE fan is unusually noisy, so that any fan I could find would be
quieter, or if I would have to be careful to shop around to find a
quiet fan. I assume that ComputerWare has already done this work for me.
There was some disagreement on just how much quieter the various fans
were -- different fans make different amounts of noise. Mike Parker
says his early ComputerWare fan is 30% quieter. Pat Mead doesn't give
any numbers, but from his description his fan is quieter than this.
Any of the fans was quieter, and none make the high pitched whine of
the standard SE fan.
I have to wonder why the standard fan in the SE is so loud, especially
when you can buy a quieter one that moves more air for only $15.
THANKS
Many thanks to Mike Farmwald <mike@mips.uucp>, Chris Borton
<borton@ucsd.edu>, Mike Parker <mikep@amd.uucp>, and Pat Mead
<patm@omepd.intel.com> for their help. Send me mail if you would
like the complete text of the replies.
-David
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David Hull TRW Inc. Redondo Beach, CA
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