Building a PC can be a frustrating process if you don't know what to look for. People often focus heavily on the motherboard, CPU, and GPU. Most people often forget to pay enough attention to other important hardware like RAM, storage, and power supplies.

Although it may seem like an afterthought, choosing the right power supply for your computer can significantly improve your PC's performance, protect it and your other components against power surges, decrease the possibility of bottlenecks, and give you more options to upgrade later down the line.

6 Trusted brands

Don't buy the cheapest PSU

While a trusted brand doesn't always mean better quality, it does mean that you will get a warranty, better quality control and testing, user-generated reviews, and at least some form of surge protection. Buying an expensive GPU and CPU means nothing if your PSU bottlenecks the entire system.

Many prebuilt PCs suffer from this exact problem because builders prioritize CPU and GPU combinations but use cheap power supplies to cut costs. You don't need the best PSU for your system to perform well, but you definitely don't want the cheapest one available as this will cause problems with your PC later down the line.

So, the next time you're browsing the prebuilt PC marketplace, skip any models that don't specify what power supply is being used, as it may be underpowered or cheaply made, decreasing the lifespan of your PC considerably or requiring you to replace the power supply as your computer ages.

5 Esthetics

Add some personality to your PC

Sometimes just choosing the best power supply isn't the only important factor that you need to consider, and if you are someone who wants to display their PC properly, you will want the PSU to fit the same aesthetic as the rest of the PC components.

This is especially true if you want to make an all-white PC build or if you want to use a fish tank-style case which gives you a 180-degree view of the inside of your PC. Not all PSU manufacturers will have their models in multiple colors, so it's important to find a trusted brand which also fits your vision for the PC

4 Connectors

Modular or non-modular

Regardless of what power supply you plan on buying, most will come with every cable you need to supply power to the rest of the components in your PC. But there are two different connector layouts you can have on your power supply. It will either be modular or non-modular.

This is an important choice if you are pedantic about cable management, as non-modular power supplies have all the cables soldered to the power supply and can't be taken out. Therefore, any unneeded cables will be tied up in your case, which might still draw a little power from your PSU, and mainly affect airflow and the appearance of your build.

You don't connect a modular PC's cables directly to the power supply; instead, you plug them in as needed. This is beneficial for a few reasons: you don't have a bunch of unused cables lying around in your case. If an important cable stops working, you can just buy a new cable instead of a new power supply. It helps reduce dust and heat buildup, and allows you to buy higher-quality connectors than the default ones.

Neither type of power supply is necessarily better than the other, so this is based on your preferences and budget. But in general, modular power supplies will look nicer if you decide to display the inside of your PC, especially if you are someone who hates cable tying all the useless cables to your PC case.

3 Form factor

Make sure it fits in your case

There's nothing worse than buying a PC component and finding out it won't fit in your PC. This is why you should pay extra attention to the size/form factor of your PSU. Unfortunately size does matter for this, and the smaller PSU form factor you need, the more you’ll pay and the less power it will provide.

There are four common form factors for PCs; ATX is the most common form factor and is what you would consider a standard PC size, Micro-ATX is smaller than an ATX and is also quite popular, Mini-ITX is the smallest form factor and used for really slim PC builds, and E-ATX is anything larger than an ATX (there isn't a standard measurement for this one).

Even if you have an ATX case and plan on buying an ATX power supply, you should still double-check the dimensions of your PSU to make sure it will fit in your case. You can use smaller PSUs in larger cases, but you probably won't be able to fully secure them due to screw placements.

2 Efficiency ratings

Better efficiency and less heat

Another important factor to consider is the efficiency of your PSU. You could have a high wattage PSU, but if it isn't efficient, then you will have a lot of heat build-up in your PC, which is not good for the rest of your components.

Investing in a PSU with a higher efficiency rating will also save you money in other areas, like your cooling system, or the cost of replacing the PSU later down the line. In general, most power supplies will have an 80 Plus efficiency rating, which means that your PSU will be at least 80% efficient while running your PC under 20%, 50%, and 100% load.

While the 80 plus rating guarantees 80% efficiency, there are different levels to this in the form of Bronze, Silver, Gold, Platinum, and Titanium certifications, which are each slightly more efficient than the level before.

If you have a low-end PC that doesn't need high amounts of power, you can probably get away with an 80 Plus Bronze certificate, but if you want a high-end gaming PC, then you will probably want to get a Gold certificate or higher, to mitigate the excess heat the system will have.

1 Wattage

More is better

Wattage is one of the most important factors to consider when choosing a new power supply. It determines the amount of power that your PSU can deliver to your system. So you should pay attention to the power needs of your PC and consider if the PSU you choose has enough power to run.

Buying a PSU that has 500 watts may be enough for some entry-level desktop PCs, but if you want to build a high-end gaming PC, then it's not going to cut it and might not even be enough to power the system at all.

If you want an efficient PSU, you also can't run it at full capacity, so you should always buy a power supply with a little more wattage than you actually need to ensure that your PSU lasts longer. It can handle upgraded hardware in the future, especially if you are considering overclocking your hardware.

As a general rule of thumb, your power supply should have at least 20% more wattage than the combined amount of the rest of your hardware. If you have a low-end PC, aim for 550–700 watts. If you have a high-end PC, you want to be in the 750-1200 watt range.

Find the right PSU for you

When building a new PC, it might seem reasonable to spend the majority of your budget on the best CPU and GPU you can get. But it is equally important to do your research on the other components of your PC as well, and this is especially important when looking at a new PSU.

You want the power supply you choose to complement your PC, and if you only want the best hardware for your PC you will need to consider every possible bottleneck, including the power supply, so don't skip out on it and look for a PSU that's right for you!