Can you use an SFX PSU in a regular (ATX) case?

PSUs (Power Supply Units) come in three sizes: ATX, SFX, and SFX-L. Typically, you only use the smaller SFX and SFX-L power supplies if you’re building a PC in a small form factor case, such as the CORSAIR 2000D, but there are a few reasons why you might want to use a small PSU in a regular case.

Firstly, it might be a purely economic decision. Say you’re moving your build over from an SFF case to a mid or full-tower. If the SFX PSU still works fine, why buy a new one?

Another reason might be a case of space-saving. You could be building something super custom and be filling up the case with a whole load of watercooling stuff – so you opt for an SFX PSU just to get a little more capacity out of the case.

However, there are a few things to keep in mind. First is that because SFX PSUs are significantly smaller than regular PSUs, they won’t line up with the mounting holes in a regular case. However, this can be solved with an adapter bracket, such as the CORSAIR SF Series™ SFX to ATX Adapter Bracket 2.0.

The second thing you’ll need to be aware of is cable length. SFX PSUs come with significantly shorter cables because SFF builds are very compact. Of course you could purchase longer cables, but you need to be very careful to ensure you get correct cables, unless you want to blow up your PC.

So, yes, if you fancy saving a buck or have other reasons for using an SFX PSU in a regular PC case, go for it. Just remember to grab your adapter bracket, and make sure the cables are long enough.