SFX PSUs are great for small form factor builds, at 4" long it will fit into those smaller systems and in the case of this SF450 from Corsair, the 17" long cables allow you to cleanly route them through the chassis.  This is an updated model, you can find the previously released SF450 still on the market and unfortunately for the 2018 model, it is about $30 cheaper. 

Is there anything to the updated model which justifies the increase in price? Check out [H]ard|OCP's full review for the answer.

"The Corsair SF450 SFX is, as you might have guessed from the "SFX" part number, a computer PSU built specifically with small form factor systems in mind. Corsair promises high power density along with "low noise," which are two qualities that many SFF builders are likely looking for. It also brings has Platinum level efficiency and is fully modular."

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