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What is a PSU? What you need to know when building a PC

A power supply unit or PSU is what connects your computer to the electrical outlet. It also supplies electricity to your PC’s internal components, including the motherboard and any other devices you add.

It’s important to get the right power supply for your PC because having enough electricity at all times will allow you to run your computer from anywhere. In many cases a cheap power supply won’t do, since it won’t be able to provide enough electricity for your computer. That being said, there are plenty of things you should know before buying the best power supply for your PC.

In this article, we will explain everything you need to know about choosing the right one, as well as potential risks and benefits of each type of PSU on the market today.

What is a power supply?

Simply put, a power supply is the device that gets your computer the electricity it needs to run. A power supply has both an upstream and a downstream side. On the upstream side, it connects to your computer, while on the downstream side, it gets connected either to a circuit or a device such as a motherboard.

How to choose the best power supply for your PC?

There are tons of factors to think about when choosing the best power supply for your PC, from compatibility to price. We recommend trying to narrow down the choices by focusing on the most important factors first. These include:

  • Power Supply Wattage: This is the amount of wattage your PSU should have. Note that while low wattage power supplies are often cheaper, they also typically have lower reliability and can’t power high performance systems with expensive components, like a top end GPU.
  • Power Supply Efficiency: Power supplies can be either 90% or 97% efficient. A lower-efficiency power supply will use more energy than a more efficient one, which is why you want to make sure to get the right one for your needs.
  • Modular: Though they cost more, trust us when we say modular PSUs are the way to go. They let you attach cables individually. The result is much easier cable management and generally cleaner build.
  • Price: Finally, don’t forget to take the price of the power supply into account when choosing the best one for your needs. You can often find inexpensive power supplies that have a low wattage and efficiency, so you need to make sure you don’t get stuck with a low-quality power supply at a low cost.

Advantages of a quality PSU

If you invest in a quality PSU based on the above factors then you’ll get a variety of benefits. These include:

  • Higher reliability: A quality power supply is more likely to last the duration of your ownership, especially if you get a more efficient model.
  • Longer warranty: While power supplies come with warranties, they’re usually limited to six months or a year. A high-quality power supply, however, has a longer warranty that can potentially be up to three years.
  • Higher wattage: A higher wattage power supply usually allows you to use your PC with more powerful components, such as a high-end graphics card. You can see a selection of the best GPUs we’ve tested in the attached guide.

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