How To Install a Power Supply


PC power supplies do fail occasionally. While you may never own the same PC long enough to have a failure, it isn't unusual for a PC aged one to three years to need a replacement. Power supply failures don't necessarily have to be total. Sometimes the power supply will appear to function but the PC experiences difficulty starting or random, sudden crashes. These are some symptoms that can result from a failing power supply.

Caution: please read our safety information.

Before opening the case, turn off and unplug the PC to avoid an electrical shock hazard. Exercise caution as there are sharp edges inside the PC and its components. Always wear a static electricity discharge strap and attach the lead to the metal frame of the case, when working with your PC's components to avoid damaging your PC. Note that some manufacturers will void your PC's warranty if you open the case.

The power supply is easily replaced. The key considerations for choosing a replacement are that the old one is removable (it almost always is), that it has the appropriate power connectors for your motherboard and that it supplies enough power for your PC's needs. See the overview for more information on selecting a power supply.

  1. Unplug the PC
  2. Disconnect all wires from the back of the PC
  3. Remove the case
  4. Unplug the power supply from the motherboard and each of the devices
  5. Disconnect the ware from the on/off switch (or remove the entire switch)
  6. Remove the power supply's retaining screws
  7. Remove the power supply
  8. Install the new power supply
  9. Connect the switch
  10. Plug in the motherboard
  11. Plug in each of the devices
  12. Replace the cover
  13. Plug in the PC

That's it! No other configuration or changes are necessary.