Skip to main content

Seasonic fanfares fanless PSUs

It's easy enough to get passive CPU and GPU coolers, but most passively-cooled PSUs have so far failed to churn out enough power at full load without doing anything inconvenient, such as blowing up.

Acclaimed PSU maker Seasonic reckons it's finally produced the first fanless PSUs that can deliver the goods. Although we'll have to wait for third-party tests to see if the new PSUs can really dish out the power without a fan, the company is making some strong claims about the fanless units.

The company rightly points out that fanless power supplies have been available for many years, but so far none of them have "lived up to the performance and quality requirements."

Seasonic claims that the PSUs' low-component count has helped to make the fanless design possible, as well as an amazing level of efficiency. The units are available in 400W and 460W versions, and both have already been decorated with the prestigious 80plus Gold award (opens in new tab).

This is a serious accolade for the PSUs, as they need to achieve at least 87 percent efficiency at 100 percent load, and 90 percent efficiency at 50 percent load, in order to get the Gold award.

The new fanless PSUs join Seasonic's X-series of power supplies, which it launched late last year with the X-650 and X-750, both of which also had 80plus Gold badges. Along with the two fanless units, Seasonic has also just unveiled a number of other siblings that will be joining the family of X-branded PSUs.

In the middle are three units targeted at the mainstream desktop market, with ratings of 560W, 660W and 760W. The company claims that the units are built using only "top-grade components," and says they will also feature a Sanyo Denki fan with Seasonic's Hybrid Silent Fan control.

This fan control system was first introduced with the X-650 and X-750, and showed the beginnings of Seasonic's fanless ambitions. The controller effectively disabled the PSU's fan when it wasn't needed, and then span it up at various speeds according to the ambient temperature.

Seasonic has also announced three PSUs at the top-end, coming with ratings of 850W, 1KW and 1.2KW. The company hasn't revealed any details about the specifications of these units, such as the amp-rating of the +12V rail, but it does say that the units "provide more +12V DC output than any comparable competitors on the market today."

Seasonic says that all of the new X-series PSUs will retain the same modular cabling system as the X-650 and X-750, as well as an upgraded DC-DC circuit design.

There's no word on pricing or availability yet, but you can expect to pay a premium for these units. A Seasonic X-750 currently goes for £152.73 (opens in new tab), so you can bet that these new PSUs to be priced in the same league. monitors all leading technology stories and rounds them up to help you save time hunting them down.