How To Install a PC Power Supply

As a computer's components are very sensitive to sudden fluctuations of electricity, a failing power supply unit (PSU) can eventually result in an inoperable and unsalvageable PC. Installing a new unit is fairly easy and can be done by regular home users. Here are some guidelines to help you.

1. Make sure the PSU is failing and needs to be replaced.  Use a power supply tester available in hardware and electronics shops. Common signs that could mean your PSU is failing or has already given out are: nothing happens when you turn the computer on, the system boots but stalls immediately accompanied by a series of short rapid beeping sounds, a burnt smell and faint smoke are coming out of the PSU, and a grinding noise is coming out of the PSU.
2. Turn off the PC and disconnect all peripherals.  Since you'll need to open up the computer's casing, it would be necessary to turn it off and disconnect all external devices such as the keyboard, mouse, monitor, printer, network cable and the power cord. The internal components can easily be damaged by static electricity. So before you begin opening up the case, it would be best to diffuse static charges from your body by holding any piece of metal.
3. Take out the old PSU.  Unscrew the casing's side panel. Then unplug all internal power cables connecting the old PSU to the other components such as the motherboard, the optical drive and the hard disk. Remember which cables connect to which component. You might want to temporarily label or list this down. With all the internal power cables disconnected, you can begin unscrewing the old PSU from its mounting, and then carefully slide it out. PSUs are generally bolted on a mounting located at the upper part at the back end of the casing. Make sure you don't hit the small exposed parts of the motherboard.
4. Put in the new PSU.  Mount and bolt the new power supply unit securely first and then connect the internal power cables. If the new unit is exactly the same model or at least a compatible one, you shouldn't have any trouble plugging back the cables. You might want to restrain any unused cables so that they don't dangle around and possibly hit sensitive components such as the CPU fan. When you're through you can close the casing's side panel and reconnect the peripheral devices.

When looking for a new power supply unit it is important that you buy one that will fit the rest of your system as well as inside the casing. A common cause of CPU and motherboard hardware damage is voltage irregularity so make sure your new power supply unit has the right specifications.