My computer is growling at me.
One of the most common problems with desktop computer hardware is the failure of cooling fans.
This usually manifests its self by making very annoying noises like squeaking or growling.
I get so many people calling me saying that their computer is making funny sounds and they think
it is about to blow up or something.
In this article, I will cover the replacement of the power supply fan. Now, many "hardware maintenance personnel"
(not the hardcore geeks) will say, just replace the entire power supply! Well, my 25+ years experience has
taught me that most power supplies will outlive the rest of the computer hardware, so why spend anywhere from
$40 to $100 on the power supply when you can replace the fan for $10 or less and about 20 minutes of your time?
To determine if the power supply (P/S) fan is indeed bad, take a look at it to see if it is even turning. If not, it's obviously
bad and there is probably an excess of heat around the P/S. If it is noisy, you should open the case and determine
if it is the P/S fan or possibly one of the other fans in the system. Maybe a CPU fan, chip set fan on the motherboard,
graphics card fan, or a case fan. On the little fans, you can touch them as they are spinning to see if the noise
changes to help determine which fan is the cause. Now, on with replacing the P/S fan...
Remove the P/S:
Above is a typical "white box" power supply marked as HIPRO.
Purchase the correct fan... These are typically an 80mm 12 volt case fan measuring about 1" thick.
Another way to ensure proper fit is to measure diagonal from the center of one screw hole to another. It should
be 4" for a P/S like this.
First, unplug the computer from the wall outlet.... VERY IMPORTANT!
Next, unplug each device from the colorful power supply leads and unplug the leads to the motherboard. If you
are unsure of where these go for re-attaching later, label each power lead and the device it plugs into.
Now unscrew the four screws from the back of the computer case to release the P/S and remove it from the case.
With the P/S now sitting on your dinning room table, or whatever you use for a work bench...
WARNING - PROCEED WITH CAUTION. Before we open the P/S case, be aware that there are components in the P/S that retain
an electrical charge (capacitors) that could produce an electrical shock if touched. Do not touch any component
or connection inside the P/S except for the fan wires as described below!
Now, if you have the "bolas" to continue, remove the four small screws as identified in the previous pic and
separate the P/S case.
Next, unscrew the fan by removing the four screws as shown. Then carefully pull the fan out and cut the two
(usually red and black) wires from the fan, leaving at lease a couple of inches attached to the P/S board.
If your new fan has a connector on the end of the wires, cut it off leaving enough length to marry up to the wires
coming from the P/S board. If the fan has 3 wires (yellow in addition to red and black) you can cut the yellow from the fan and ignore it.
The yellow is for the RPM speed sensor which most power supplies do not support.
Now place the new fan into the case with the air flow pointing out. Most fans have an arrow molded into the black plastic
housing that indicates the air flow direction. Turn the fan to position the wires where they will reach the wires still connected
to the PS board. Screw the four mounting screws into the fan... do not over tighten.
Next, if you have thermal/heat tube wire insulation, as shown in next pic. place about a 1" section on each wire, strip the
wires and twist connect the red wire to red and black to black... pretty simple. Use a heat source on the thermal insulation,
or, if you do not have thermal/heat tube, just use electrical tape and tape up each connection.
Now, slap it back together by placing the P/S cover on, mount it in the computer case and re-connect all power connections.
Power it up and stand back... I mean, enjoy your new quiet and cool running power supply.
Article Date: 10/16/2006