Power Supply-related FAQs

There are various reasons why a computer will shut down. Chief among these is component overheating. The most common cause of computer overheating is a fan going bad and failing to cool down a component. Most computers have power supplies similar to this one:

When a PSU fan goes bad, it is not able to cool down the power supply hence the device will heat up. The excess heat generated by the PSU will add to the overall temperature of the system unit. If this failure is not corrected, the PSU will become damage. A damaged PSU can, potentially, damage the components as well as the motherboard, itself.

If your system appears to be exhibiting an, abnormally, high temperature and you suspect that the PSU's fan has gone bad but are not sure, there is a test you can perform which should prove weather the fan is working or not. This test is called, “The PSU Paper Clip Test.”

The first things we need to identify are the main power connectors that run from the PSU and attach to the motherboard to supply the voltage and current that your motherboard and its components need. Most power supplies have a 20 or 24 pin ATX Connector like the one shown in the picture on the left and a 4 pin ATX Connector like the one shown in the picture on the right:

These connectors are needed by your motherboard in order to function properly. As mentioned above, they supply the proper voltages and currents that the various components attached to the motherboard need in order to work properly. These components include, the motherboard itself, the CPU, the memory modules, the hard drive and the optical drive as well as any video cards that your system my use.

To perform the PSU Paper Clip test, we’ll need to examine the power supply connectors closely and find the one that has a lone green wire. Ninety nine percent of the time, this green wire is located on pin 14 on the bigger connector. In addition to the green wire, locate the other black wires that are present in the connector. Here’s an image of the wires in question:

Once the wires are located, you will need a paper clip such as the one shown here:

It is now time for the fun part. First you need to reshape the paper clip into a shape that is similar to the letter C as follows:

Once this is done, make sure that the power cord is NOT connected to the power supply then connect one end of the paper clip to the green wire and the other end to one of the black wires present on the connector as shown below: