A 400W PSU seems a little under-powered when compared to the kilowatt PSUs that are commonly reviewed but there are not many systems that actually need that amount of power.  Seasonic has designed their X-400FL Platinum 400W to provide great power, efficiency and extra features in lieu of providing huge amounts of power.  The PSU is fully modular and is able to provide an impressive 33A combined from it's four 12V rails, with an absolute minimum of ripple even during the most intense parts of [H]ard|OCP's testing.  At $120 it is a little more expensive than other similar PSUs but with the outstanding build quality of the PSU it is worth it.

"This new Seasonic PSU touts Platinum efficiency, a fully modular design, and a host of other enthusiast-worthy hardware features that will ring true with those looking for a what might be "the best" 400 watt PSU on the market. For those of you looking to build that truly powerful HTPC, this PSU also offers silent operation."

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CASES & COOLING