4.PC Power Supply: How to Choose the Right One for You--from intel

Form Factor and Cabling Preferences

As with most PC hardware, there's a huge variety of options when it comes to what your power supply looks like.

One consideration when it comes to PSU form factor is the physical size of the unit. For the vast majority of desktop PC users, standard ATX power supplies should be fine, though you’ll still want to make sure your PSU will fit in your case by checking the appropriate clearances.

If you’re a small form factor PC (SFF) enthusiast, you’ll want to do a little more research to make sure your PSU will fit. There is a wide variety of SFF PSU sizes, like SFX, CFX, and more, so make sure you find the PSU that works with your case, no matter how small your PC.

Another important distinction when it comes to the physical attributes of your PSU is whether it’s modular or non-modular.

A power supply operates by converting energy from a wall socket and routing that power to each of the individual components in your system through a variety of cables. If your power supply is non-modular, these cables will already be soldered to the circuit board, meaning you don’t get to choose the cables that will be in your build. All the cabling, even the ones that you don’t use, will need to be stored in your case.

There’s nothing inherently wrong with this from a functional perspective, though poor cable management can lead to less efficient airflow, so you’ll want to be sure those extra cables don’t get in the way.

Modular power supplies, on the other hand, don’t come with the cables attached. This changes the installation process, as you’ll need to connect each cable to the PSU and the component that it is powering, but that also means you can optimize for fewer cables. This results in a cleaner build and potentially better airflow. Most people aren’t going to use every connector provided by the average power supply, which makes modular units a little more practical, as well.

There’s also a third, in-between option, creatively called a semi-modular power supply. These are exactly what they sound like: Some of the most frequently used cables are attached to the PSU, while some you’ll have to connect yourself.

For modular and semi-modular power systems, keep in mind that you do not want to mix and match cables from other manufacturers, or even different models from the same manufacturer, unless stated otherwise. Though the cable-ends that connect to the components in your build are standardized, the end that connects to the PSU isn’t, meaning different brands could have different connections. That’s why you should only use the cables that came with your power supply.