The Power Supply

A Computer's Power Supply

This is the power supply. The purpose of your computer's power supply is to take in the high-voltage AC power from the wall outlet and convert it to usable low-voltage DC power. The power supply also spreads power to the motherboard and all the drives in your computer through the mess of colored cables inside the computer.

The Power Supply's Connecting Cables

PC Main Power Cord

This cord plugs directly into the motherboard and supplies power to everything that plugs into the motherboard through its other ports.

Auxiliary Power Connector

This power cord supplies additional power to the motherboard. Not all computers will have additional connectors like this. The best way to tell where things should connect between your motherboard and your power supply, if you ever need to replace the power supply, is to check the manuals for your motherboard, which will tell you what each port is supposed to connect to.

Molex connectors

Technically called 4-pin peripheral connectors, the name “Molex” comes from their manufacturer. These connectors supply power to your hard drives and disk drives, and there are multiple plugs on each cord in most standard power supplies in order to maximize the number of peripherals you can connect while minimizing the amount of space taken up by cables inside your computer. If you find a plug on one of these cables that is smaller than the rest, it is the connector that supplies power to the floppy drive, if your computer has one.

The Front of the Power Supply

Power Supply Fan Port

Behind this grill, you can see the interior of the power supply. This is a fan port that allows air to be pulled over all the power supply's electronic components, keeping them cool.

Main Power Connector

This is where you plug the power cable from your wall outlet into your computer through a hole in the case. The power from your wall outlet supplies power to your computer through this plug.



Now that you know the basics about the power supply, you can: