What is it?

Your power supply or PSU is the one part of the PC that plugs directly into the wall, and distributes that power to every other component. 

 

 

What specs should you look out for?

  • Power Output: The amount of power your PSU can put into the PC, measured in watts. Most modern units range from 450W to 1600W

  • Efficiency Rating: How well the PSU can prevent the loss of power as heat. Higher efficiencies will cost less to operate and let your PC run cooler, though they will cost more initially. All PSUs use a rating system called the 80 PLUS certification rating.

  • Protection: Many PSUs will come with built-in protections for scenarios such as over voltage, under voltage, short circuit, overheating, and brown outs.

  • Modularity: PSUs can be either non modular, semi modular, or fully modular. Non modular PSUs will have cables hard wired into them, while fully modular ones come with fully detachable cables. Fully modular units allow for a cleaner look and much easier cable management, but can be more expensive than the alternatives.

  • Fan: All modern PSUs come with integrated fans. Some units come with a Variable RPM mode or some variation thereof, where the fan's speed will change based on the temperature. These fans can also vary in size, typically being either a 120mm or a 140 mm variant. Larger fans tend to be quieter and more efficient, but the size you choose will depend on what fits in your case.

 

What do I recommend?

One of the most important things is that you get a PSU with a much higher wattage than your PC requires. My own PC only takes about 475W, but my PSU can output 850W. This does two things for you: it protects you in the case of a power surge, where one or several parts may start consuming more power than they are supposed two, and it future-proofs the part by compensating for the increased power needs of upgraded parts. I would also recommend buying a modular PSU if you can spare the extra money. It may not seem to make much of a difference, but it makes cable management a lot easier and again allows for easier upgrades later on.