Seasonic S12-500 & S12-600 Power Supplies
 

Seasonic is one of the longest-established makers of computer power supplies, and their products have consistently won respect from SPCR. The S12-430 we reviewed around two months ago turned out to be the one of most efficient fan-cooled PSU encountered, and also the quietest by a pretty big margin. Early production samples of the highest powered models in the S12 line, the 500 and 600, were also on hand at the time of the review, but Seasonic requested that we delay the review until newer samples were made available. A production change in the fan was coming, and this would affect the entire S12 line.

The Seasonic S12-500 and S12-600 differ from the lower powered S12 models more than just by power rating. These models actually use a different circuit design than the lower power models. Their model number, SS-500/600HT Active PFC F3, is different from the rest of the S12 line, SS-330/380/430HB Active PFC F3. The latter models feature upgraded variants of the circuit design used in the now-discontinued Super Tornado, while the 500 and 600 are entirely new. There is a third model, SS-400HT Active PFC F3, that logically belongs with the S12-500 and S12-600, but for whatever reasons, it appears to be unavailable for the retail market at this time.

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