Seasonic X-Series: X-400FL Silent Power Supply Review

Seasonic, long known for making excellent power supply units has gone silent. Not just quiet, silent. It's new 400 watt unit comes to the consumer complete with no fan. Now let's see if the new silent Seasonic is worth your hard earned cash.


In the power supply realm when consumers think of quiet and efficient power supplies one of the first companies that comes to mind is Seasonic and today we have our fifth crack at a Seasonic branded power supply. Today's review covers the launch of Seasonic’s newest addition to their X-Series line of power supplies the "fanless" X-400FL (SS-400FL Active PFC F3). Being that this unit has no active cooling, we are looking at what quite possibly could be not just a relatively quiet solution but what could actually be a totally silent power supply from Seasonic!

Seasonic is one of the older companies producing consumer power supplies having been founded in 1975 and entering the PC power supply production market in 1980. During that more than 30 years as a company Seasonic has cultivated lines of power supplies that are today some of the standard bearers for efficiency and quiet computing. This focus, and its reputation for quality, has lead to a real explosion in production as Seasonic can be found providing OEM services on various model lines for Antec, Corsair, XFX, and of course under its own Seasonic brand.

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Fanless Wonder?

For a long time now Seasonic has been considered by many enthusiasts to be one of the premier manufacturers of quiet power supplies, however its offerings in the fanless niche have been almost non-existent. Today though, Seasonic launches two new fanless units which rectify that situation and present us with a niche product that we have not covered in our reviews before. Given this units niche fanless design we are apt to speculate that our Audio Impressions section of this review will likely be a total of one sentence long. As long as it's a good sentence though it likely won't be too much of a letdown wink Given that this is our first review of a fanless unit, let's start off by seeing what exactly Seasonic has to say about this X-400FL unit:

Silence defines the X-400 & the X-460 power supplies. Taking advantage of the benefits derived from the 80PLUS GOLD level of efficiency and the use of high-grade components, these power supplies run cool and run silent, perfect for your Home Theater PC (HTPC) and other applications where "silence is golden".

Featuring a design of "DC Connector Module with Integrated VRM", the X Series is set to achieve both near-perfect DC to DC conversion and fully modularized design without compromising efficiency. After a long wait, finally there is a product that delivers the complete package, ultra-high efficiency, greatly improved dynamic response, and customizable cable arrangement that is tailored to meet any individual’s needs.

Now that we know what Seasonic expects from this power supply let’s see what we have to look forward to when we purchase the X-400FL in terms of documentation, accessories, cable count, rail layout, output characteristics, and general build quality.