There you are building your PC, you’ve assembled a collection of components such as highly powerful GPU and CPU, a lightning-fast SSD, and a sleek case. You have not yet decided on a PSU, however, and you are beset by a choice: ATX or SFX? If you are a first-time builder, this choice might be confusing. What do these terms mean and do they even matter? 

In a previous article, we outlined the meaning of ATX and how to know if you should buy an ATX PSU. In this article we are going to discuss SFX, what it means and whether it may be the right choice for you.

What does SFX really mean? 

SFX is an acronym for Small Form Factor. The main feature of an SFX PSU is right there in the name, its size. An SFX PSU is significantly smaller than an ATX PSU. How much smaller? A standard ATX PSU is 150mm x 86mm x 140mm, a micro ATX PSU is 150mm x 86mm x 100mm, and an SFX PSU is 125mm x 63.5mm x 100mm. As the measurements show, an SFX is a major space-saving improvement over even a micro ATX PSU.

The smaller size of the SFX PSU means that it has greatly improved power density over its ATX counterparts. Power density is a measurement of wattage per liter, and higher power density means more power in a smaller volume. For an example of exceptional power density, check out Cooler Master’s new V SFX Platinum. With units available up to 1300W and a power density of 26.8W per cubic inch, the V SFX Platinum is the PSU with the highest power density on the market today. 

How do I know if I need an SFX PSU?

Now that you know SFX PSUs are smaller and thus have a higher power density than larger PSUs, the next question is: do you need one? This question will be primarily answered by what kind of PC you want to build. Do you want to build a hulking, powerful beast of a machine with multiple graphics cards and a full-size ATX motherboard and case? Or would you rather go for something smaller, sleeker, and subtler? 

A mini-ITX case is one of the smallest PC case sizes available as it supports the mini-ITX motherboard. For such a build, an SFX PSU is ideal and in fact necessary as mini-ITX cases are too small for ATX PSUs. One such case is Cooler Master’s MasterBox NR200P. At 376mm x 185mm x 292mm, the NR200P is a great example of a mini-ITX case that would work well with an SFX PSU.

Now, does that mean SFX PSUs only work with smaller cases? No, you can use an SFX PSU in any case size, as long as you make sure the cables are long enough to reach every component. For example, the V SFX Platinum comes with a bracket that allows it to fit in an ATx case.  Still, it is true that the SFX PSU works best with smaller cases such as a mini-ITX case. 


Whether you should choose an SFX PSU is largely determined by your own preferences regarding the overall size of your build. 

Cooler Master has a growing selection of SFX PSUs. As the first PSU to support up to 1300W, the V SFX Platinum represents a new industry standard in high power density PSUs, pushing the limits of SFX farther than ever before with features such as ATX 3.0 support, overall component miniaturization, and improved structural integrity. A small form factor PSU such as the V SFX Platinum fits perfectly with a mini-ITX case such as Cooler Master’s MasterBox NR200P. A small but mighty case, the NR200P includes features like triple-slot GPU support and multiple motherboard compatibility options. For more information on the V SFX Platinum and Cooler Master’s selection of other SFX PSUs, please visit the following link: https://www.coolermaster.com/en-global/products/v-sfx-platinum-1300/

Be the first to knowJoin our mailing list for special offers, new products and contests.