Computer NOISE!             One solution...

I hate it! One of my biggest peeves about DOS computers is that almost none
of them is anywhere NEAR being quiet. Many have noisy hard disks, but the
biggest culprit by far is cooling FANS! These cheap little wonders create
a nice high pitched whine that permeates the air. On some machines with
cheap power supplies it's REALLY bad. Even "high-end" brands suffer here.
Most people seem to get used to it. Kinda like getting use to a train going
by your bedroom window. I have never gotten used to it. It seems to increase
stress or "tension" in the air. Well, I solved my noise problem almost
completely. What follows is how I did it. I thought it would be nice to share
this solution with those out there who feel like I do. Pardon the grammar,
typos and language abuse to follow. I will say one one thing right off...

          "I'm typing this in PEACE and QUIET (aahhh)"

Now, why the wordy diatribe?

I work in an office with several others and we live with our computers 8+hrs
a day. I finally got fed up with the fan noise on my 486/33 tower case. It has
a top-of-the-line power supply, but we have quite a mix of power supplies in
our office, and all are noisy. Some VERY noisy. I tried several brands of
fans, thermostat controlled fans, and a number of enclosures around the
computer case. None of them really got rid of the noise. Even with thermostat
controlled fans they have to turn fast enough to cool and a 486 gets fairly
warm. My full-size tower case is not too packed, so that really wasn't the
problem. I removed the power supply out of the case and ran it alone. It was
much quieter. The fan running alone (detached from the power supply) was very
quiet. Hmmm. Seemed simple. The fan vibrations are transferred to the power
supply case then on to the computer case, where they are very hard to dampen.
The solution, I figured, was to physically isolate the fan from the case...

Here is my cheap but effective solution:

WARNING! Messing around inside the power supply could be dangerous, plugged in
or not. It can also cancel any warranty it or the computer may have. These days
if you even touch a screw on a device your warranty may be dropped like a hot
potato. On the other hand, if you are adventurous with hardware, my fix
doesn't actually do any permanent damage and is easy to do and UNDO
(read: cover up). For the lawyers, I, of course, cannot accept ANY
responsiblity for the results of trying this idea. Use at your own risk.
(read: CYA)

That said AND if you hate the NOISE as much as I do, forge ahead.

FOR GENERIC DOS DESKTOP COMPUTERS: This solution involves removing the
fan from the power supply and totally isolating it from the computer case.
If that freaks you, bail out now... This is really a very simple job, but
I'll go into tortuous, wordy, ad-nauseum extreme to explain it. I KNOW
a lot of it is common sense but I'll go over it anyway.

Unplug the power cord, let the computer sit unplugged for a couple of
minutes (1 hr for CYA) to let the caps discharge, then open up the computer
case. *FIRST THING*, check to make sure this is a power supply you can take
the cover off of. Otherwise, pack it up and ignore this doc. You can tell
if it can be taken apart if the screws holding the inside case together are
ones you can remove such as Slot, Phillips, Torx, etc.

If you CAN take the power supply apart, remove it from the computer case.

(*Note: Taking the power supply out of the case is only necessary if you can't
reach all the screws that hold the power supply cover on. If you can take the
cover off while it's still mounted in the computer case, by all means, do.)

This is usually a matter of unplugging all the power leads to the different
peripherals (floppy, tape drive, hard disk, etc.). No magic here, the plugs
are all the same (usually) and can only go in one way. Go easy on the
connections. Don't tug too hard. Wiggle 'em out if you have to. The best way
to keep from messing up is to label which plugs went to which devices with
tape or something.

Next unplug the two connections going to the motherboard. Here, it's always a
good idea to label which plug went into which socket since they are normally
the same size and number of pins. The motherboard power plugs are a bit tricky,
you must pull them part way out, lean them a little, then unhook them.
TIP: Whenever you are working near the motherboard with tools or your hands,
use a static leash or frequently ground yourself to the case (preferrably
grounded itself) by touching it. Those static sparks can do a bit of damage
if you are careless. But don't let that shy you off. Again, no magic here.
Motherboards and most electronics today are really very durable and can take
a lot of abuse (just watch how some are put together sometime...). It's easy
to stay static-free.

Next, remove the 2 to 5 screws holding the power supply to the computer case.
These are usually on the outside of the case on the back by the fan grill.
Some may have screws on the inside too, but most generics don't. Don't unscrew
the four screws holding the intake grill on yet. Carefully remove the power
supply from the case.

Now, remove all the screws from the power supply cover and remove it.
Always treat the inside of a power supply like it was hot, just to be safe.
You should now have easy access to the fan. Most fans just have two leads,
usually red & black, snaking over to a plug on the power supply circuit
board. Some fancier fans have a "trim pot" to control fan speed manually.
That's usually the doohicky with a bare splined shaft poking out the side
of the power supply case.

At this point there are a number of things you can do.

Here's what I did: I unplugged the fan first. Sometimes the plug has tamper
evident or anti-vibration goop on it so work the plug out carefully. I then
removed it from the power supply case by unscrewing the four screws that hold
it and the intake grill on. I reinstalled the wire grill with some small
machine screws and thread-locking agent to prevent the nuts from working loose.
This keeps roving fingers out of the power supply innards. I put the power
supply case back together and reinstalled it back into my machine, without fan.

I then attatched about 4 feet of 4" diameter white plastic corrugated
dryer hose to the grill opening. For a quick and dirty connection I used
some stuff called door & window caulk that comes as a thin tape in rolls.
There are other products like it, sometimes called window glazing tape
or caulk. This stuff is SUPER sticky, never hardens and can be fairly easily
removed later if it's the stiff kind. I just made a nice fat bead of it and
plastered the end of the duct to the back of the computer over the grill
opening. It's held so well (many months so far) that I haven't attached it
more securely yet.

Anyway, I happened to have an older AC powered 5 inch EDM brand fan with a
5" to 4" inlet cone in my junk box. Where I got it, I don't remember, but it
was an accessory cooling fan for an old 8088 machine. It moves a lot of air
and is super quiet when running alone. I stuck the fan to the end of the
dryer duct with the sticky gunk, set it on the floor (no dust problem because
the fan is sucking air OUT of the computer through the duct), plugged 'er in
and fired up my computer...

Ahhh...Sweet SILENCE!  Blissful QUIET!  WOW!

As an added bonus, since my external fan is AC powered with a cord of its
own, it stays running even if I turn my computer off, keeping the components
cool at all times. This probably helps reduce some thermal shock. Who knows?

My co-workers, previously scoffing at me as being too picky and going to
extremes about this "noise thing", immediately came over and stood in AWE
of my now whisper-quiet work area. Well, maybe not AWE, but almost. They
thought my machine was turned OFF, but the power light told the tale. Even
though they thought the original noise was minor, it was VERY noticeable
when it was gone. Needless to say our office is now MUCH quieter due to
a number of the machines being given the "quiet" treatment. It has really
seemed to reduce the stress level since we pretty much live with these damn
boxes more than with our own families (we are, you guessed it, programmers?).
Score a direct hit for ergonomics! Nuke yet another stress inducer. Wipe out
that background, insidious, brain-numbing NOISE!

For those who have waded through all this tedious verbiage to reach this
point and are saying "Ya, well I don't have a 5" AC EDM fan with a 5" to 4"
reducer", I offer these ideas, all of which I have done and work well.
These ideas involve, yes, SOLDERING, or maybe little wire nuts in a pinch.
Once the power supply is opened up, clip the red & black leads halfway
between the fan and the plug in the circuit board. This should leave plenty
of lead to work with on both ends. Remove the fan and reinstall the grill
in the opening for safety. By the way, I would remove the fan even if you
have a seperate AC fan, since the unplugged, unused fan would rotate just
from the air passing by it, possibly vibrating, and cancel out what we are
trying to do. Not to mention it impedes free air flow. We want the fan OUT
of the computer case altogether.

To continue: Grab yourself a stranded, insulated, twisted-pair of wires of
similar or slightly larger guage than the leads on the fan. This extension
pair should be a little longer than the dryer (or whatever) duct you are going
to use. Make sure the two wires on the extension are tightly twisted to
prevent any possible electrical noise. Color matching the extension wires to
the fan wires is cool and "tidy" but not mandatory. Make sure that in the end,
red (or whatever) on the power supply goes to red on the fan and same for the
black or else the fan will turn the wrong way. This won't hurt it, but the
blades are usually optimized (blow harder) for only one rotational direction.
(Unless it's an internal AC, not DC, fan, in which case polarity is not
an issue.)

Solder this twisted-pair lead to the two wires in the power supply. Securely
tape up or better, shrink-wrap the connections. It gets warm in the power
supply and plastic electrical tape can sometimes unravel in heat. Quick & dirty
connections can be done with carefully done wire nuts. They hold well in heat.
Why belabor the connection stuff? Well, your computer will rely on these
connections being good and solid and heat/vibration proof. So I belabor.

Snake this lead out the grill and cable-tie it securely in place with a little
slack left inside the power supply. That lead should be able to take a pretty
good tug without pulling on the wires inside the power supply. Also, make sure
the fan leads inside the power supply are clear of all components. Cable-tie
or glue them out of the way if needed. Reassemble the power supply and
reinstall it in the computer. Run the outside fan lead though the duct and
attach the duct over the power supply grill opening with sticky gunk or a
more elegant way if you want. Connect the extension lead to your original
fan leads (watch that polarity) and attach the fan to the end of the duct.
Make sure the extension wires cannot get sucked into the fan. Use some sticky
gunk to stick it to the insides of the duct or punch a cable-tie through the
plastic around a rib (in dryer duct) and around the wires and snug up after
the fan is attached.

Make sure the duct you use is very soft and flexible to cancel vibrations.
Regular dryer duct is good, durable and easily available. A rigid duct would
transfer the fan vibrations back to the computer case and make noise.

Oh, almost forgot, what about those with a fan speed control trim-pot in the
power supply? You can leave the control in place and cut the fan leads
between it and the fan and do just like described above. You could also
desolder the fan leads from the pot and solder the extension leads right
to it. I recommend running the fan at maximum anyway so you don't really
need it and could bypass it altogether. If you chose to leave it, just crank
it up and forget it. Make sure you turn it the right way by testing it BEFORE
taking anything apart. If you are a real hot-shot you could fabricate duct
ends for both the computer and the fan end and move the speed control out to
the fan-end housing. But then you would probably make your connections with
custom cable ends too. I don't need to tell YOU how to do it.

I used 4 feet of duct because I have a tower case and wanted the fan to rest
on the floor. Regular desktop cases could probably use one foot or less.
The idea is to really isolate the fan from the case so don't go too short.
Don't get the duct too long either or air friction can really reduce the fans
ability to draw air and not cool the computer well enough. Probably 1 to 3 feet
if you use the fan (if it's healthy) that comes with the power supply. Always
monitor temperatures for a little while after doing this modification. The
output air should flow well enough to feel easily with your hand and just
mildly warm at most. Sorry, I don't have the exact temperatures and flow rates.
They could be found out with a little study, but if you roughly match the flows
and temps of the fan when it was IN the case to how they are when the fan is
at the end of the duct, you will be just fine. Not so? One more thing, make
sure the fan is sucking air OUT of the computer case which is the usual way
it's done. You could go the other way too if the computer case is designed
to be cooled that way. I mention this because the pancake fans are easy to
stick on the end of the duct the wrong way (would probaly work fine anyway).

There you have it. This noise solution works extremely well, but is not
very aesthetically pleasing. In my case all the duct and wires tuck out
of sight on the side of my desk and a wall. No problem. If you are out in
the open bull-pen style, maybe you could paint the duct flourescent or
something. Some hardware types or management might freak at this concoction,
espousing the usual default mantras about all the damage you could do, that
it's really a tricky, magic business that can only be handled by experts, blah
blah, blah. Negation of warranties could be a big issue. Hey, they or you
could say it's just plain butt-ugly. In any of these cases you are out of luck.
You be the judge. If you REALLY hate that noise, you'll find a way. Fans and
ducts are bone-simple, cheap and dependable (usually) so what's the big deal.
Maybe somebody should just get wild and engineer a TRULY quiet power supply or
better yet, computer. I won't hold my breath.

Now for the "sqeal" in my monitor... Probably not until big color TFT's,
FED's or something similar get cheap enough.


Comments, criticisms, horse-whippings  to  Cliff Brown CIS# 70253,1442   










