One of the most crucial components of any PC is the power supply unit or PSU. Every component from the motherboard to CPU and even hard drives need to be connected to an adequate power supply to function properly, and the AC power that comes from your wall outlet power cord can’t power them directly. Instead, you need a DC power converter to regulate the different low voltages that each component requires. That’s why a reliable DC power supply is an essential part of every desktop computer. In laptops, the wall charger acts as the adapter that converts AC into DC power, and internal voltage regulation circuits handle the rest.
While multiple power supply options may work for your setup, determining the best specific power supply for your desktop PC can help to reduce build costs and increase system efficiency. To find the ideal PSU for your build, you will need to consider factors including wattage, connector compatibility, and form factor.
What Power Supply Wattage Does My PC Need
When choosing a PC power supply, the first important factor to consider is the power provided by the device measured in wattage. The most popular sizes of power supply are 750w, 500w, 850w and 1000w. 750 watt power supplies are the most common and are sufficient for most computers while leaving ample room for future upgrades.
Power supplies for gaming PCs may require a higher wattage because of their powerful graphics cards and processors. Other features commonly found in power supplies for gaming PCs are addressable RGB LEDs or support for multiple graphics cards. The best way to determine how powerful your PSU needs to be is to look at the other components in your computer and how much power they will draw.
The second primary specification to look for when choosing a PC power supply is the device's 80 Plus certification. Often, EVGA, Corsair or other brands of PC power supply will have a standardized 80 Plus certification. The available 80 Plus certifications in ascending order of efficiency are 80 Plus White, Bronze, Silver, Gold, Platinum and Titanium. These ratings tell you the operating energy efficiency of the device and can help to narrow down the perfect power supply for your PC. For example, a 600 watt 80 Plus Gold power supply may outperform a 750 watt Bronze certified device for specific tasks.
Connectors Form Factor and Other Things to Know
Another major factor to consider when choosing a PC power supply is how the device connects to other components. This has important implications for your PCs cable management and aesthetics, as well as which components you can use in your build. Modular power supplies are the most customizable because power cables can be added and removed easily, so you are only using the connections needed in your PC. Cable management and case organization are much easier with modular power supplies due to this key feature.
Most modular PSUs today have a relatively standardized set of connectors that provide a range of options for powering your components. However, some high end GPUs require additional PCIe connectors, so it is always a good idea to check the type of power supply connectors required for your specific components, no matter what type of PSU you are using. In addition, note that you should only use OEM cables to connect your modular power supply to other PC components. Modular PSU cables, while they may be physically compatible, aren’t always interchangeable because the pin layouts on the PSU can vary. Using a non specified cable may cause electrical damage to your components, and the damage likely will not be covered by any warranty.
Non modular power supplies can function in the same capacity as their modular counterparts, however, cables come pre connected to the device and cannot be removed. While non modular PSUs can come with some substantial cost savings, they often require carefully planned cable management since you won’t be able to remove cables you don’t need. Semi modular power supplies are a cost efficient compromise because they have some pre assembled cables such as the 24 pin connector for the motherboard, as well as removable ones.
A power supplys form factor, while less varied than other specifications, is undeniably important. If your PSU doesn't fit inside your computer case, none of the other features will matter. Most commonly, you will find ATX power supplies, which are considered full size and fit in almost any consumer PC. Smaller form factors do exist, such as SFX, Flex ATX, and TFX. These are useful for anyone who wants to build a more compact PC. To find which power supply form factor your PC supports, you can check the specifications of your case.
Finally, cooling and airflow are other key considerations for anyone buying a power supply for their PC build. All computer power supplies generate heat as they operate, which is why most come with cooling fans built into the unit housing. That means it is also important to position the power supply in a location within your case where it has unobstructed airflow so the fan can work as intended.
Not sure which power supply is the best choice for your PC? Micro Center experts are happy to help! Visit our help center for tons of resources about choosing the right PC components for your build or chat live with a Micro Center employee for personalized advice.
