How to Install a Power Supply

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Cost of Repair

In this tutorial I will show you how to install a power supply into a desktop computer. The power supply is what converts the AC voltage from your wall socket to DC voltage for your computer to use. It is quite common for a desktop power supply to fail so don’t be surprised it happens to you. The steps the remove and install the power supply unit are simple but sometimes pulling out the power cables can be difficult, especially with a molex power connector. If you’re replacing a failed power supply then I would recommend you blow out your computer case before proceeding. Also, make sure that the wattage and connectors of your new unit is sufficient and compatible with all your computer hardware.


1. Unplug the power cables from all the computer components like the motherboard, hard drive, optical drive, etc…

2. Once all the cables are unplugged, then proceed to unscrew the power supply from the computer case. There are usually four screws that will need to be unscrewed. When you are unscrewing the last screw make sure to support the power supply or it might fall and damage some components.

3. When you unscrew all the screws then remove the power supply from the case.

4. Grab your new power supply and screw it onto the computer case

5. Attach all the power cables to all the hardware inside the case.

6. Plug in the power cable into the power supply and your done.


– If the power supply has any unused cables then use a cable tip to attach them to the main strand of cables to allow for proper airflow inside your desktop case.

That’s it! It’s really that simple. We hope the tutorial “How to Install a Power Supply” has helped you with your computer repair issue.

You can watch this tutorial on video by clicking the play button below. For the full screen version click the second button from the right on the video.


If you need more help regarding this “How to Install a Power Supply” tutorial then let us know by visiting our Repair Questions page.