Power Supply Unit

What does it do?

A Power Supply Unit (PSU) is the component in a desktop PC that takes the electricity from the power socket and distributes it to the other components within your PC.

How does it work?

Different machines require different amounts of power. A basic PC that lacks a dedicated graphics card, and has only a single hard drive or SSD, will need a lot less power than a high-end computer housing a number of demanding components. This means the basic machine can get by with a cheaper PSU that supplies a relatively low amount of power. However, if you intend to add more components in the future, you might also need to upgrade your PSU.

What are the specs?

The key specification of a PSU is how much power it can supply (measured in Watts). You need to make sure that any added components don’t draw more power than the existing unit can handle. Alternatively, if you’re upgrading your PSU, make sure it’s powerful enough to work with your current setup and any upgrades you might make in future. PSUS tend to range from 450W to 1,000W – the Corsair RM750 (pictured), for example, e supplies 750W. Not surprisingly, more powerful PSUS are more expensive, so it’s worth having enough headroom for future upgrades but not overdoing this so that you’re spending more than you need to. To find out how much power you may need, use the calculator at www.snipca.com/40356.

Can I change it later?

Yes. A PSU in a desktop PC is easy to remove and replace. Just make sure that the new one is powerful enough, and that your existing cables are compatible with it.