Seasonic Super Silencer 400 - ATX12V 1.3

Viewing page 1 of 5 pages. 1 2 3 4 5 Next

July 16, 2003 -- by Mike Chin

Product Seasonic Super Silencer 400 PSU (ATX12V v1.3 compliant)
Model SS-400AGX Active PFC rev 1.1
Manufacturer Sea Sonic Electronics
Supplier Sea Sonic Electronics USA
Price US$99

Readers who have scoured the SPCR power supply section will know that the Seasonic SS-300FS-APFC was our first unsolicited review sample. It was just after Seasonic's entry to the US retail market. Beneath its plain Jane exterior, the SS300-APFC turned out to be a functional beauty, with excellent efficiency and a highly intelligent thermal fan speed control circuit (S2FC) that remains the one to beat even today, a year and 12 PSU reviews later. The 300 went on our Recommended PSU list, of course (as did the 400W version of the same, the non-PFC 300W and the 200W SFX version as well; they all feature the same excellent S2FC fan controller.)

Seasonic's engineering and marketing teams have not been idle. An e-mail press release about a new line of Super Silencer and Super Tornado PSUs came in a couple of weeks ago, along with an invitation to review these new models, which was naturally accepted. Not much later, UPS delivered a carton of samples.

The Super Silencer line is the next generation of the SS-xxxFS-APFC line we're familiar with. The Super Tornado is a 120mm fan PSU of the type first seen with the Fortron brand, which has become quite popular with SPCR forum members.

This review focuses on the Super Silencer 400; there are 3 others in the line: A 300W, a 350W and a 460W model. Apparently, there will be a period of transition during which the SS-xxxFS-APFC line coexists with the "Super" line. In some markets, the Super series may not be introduced for some time. It has been available in Taiwan since some time in June and also in Japan since the beginning of July. In the US, Seasonic's "Super" line will be available very soon at Fry's Electronics.

Silicon Acoustics also sells Seasonic "Super" PSUs


While the SS-xxxFS-APFC generation PSUs featured a pleasant box, it was hardly an example of hard-hitting modern retail packaging. It is evident from a single glance at the new packaging that Seasonic marketing have done their homework. The Super Silencer box is designed to grab your attention and sell you on its features as you ponder your purchase in the store. (There's enough reading material on the box to last a quick lone geek lunch!) Actually, the box is good enough to explain most of the features: All the images in this section come from the box.

Aside from the 400W designation, the main cover photo immediately tells you that this model features a proper wire grill and automatic universal AC input voltage. Then there are the phrases "Ultra Quiet" and "Energy Saving" (One wants to ask why throw ultra into the mix when super is already in the name?!)... and 7 icons that include the text:

1) 80% Efficiency. In PSUs, this specification refers to how much power is lost when converting AC voltage to DC voltage. A voltage and power output level is usually specified. In a separate e-mail, a Seasonic engineer informed me that the 80% efficiency rating is for 240V, at full power. The rating for 120V is 78%; it is almost always lower for the 120VAC input. Regardless, these are the highest efficiency numbers I have seen claimed for any PSU meant for a PC. The most common number seen is 65%, with 70% being the "standard" number claimed for more high-end PSUs.

2) Active PFC - 99%. The high AC/DC conversion efficiency is combined with Active Power Factor Correction for a PF of 0.99. This results in extremely low energy waste, as explained in detail on the back of the box.

3) Free Input. This refers to automatic AC input circuitry which allows the unit to run without manual switching at any AC voltage from 100V to 240V.

4) S2FC - 25 dBA. It's the fan control circuit from Seasonic's existing PSU series, and they're claiming a noise level of 25 dBA, although no distance or power level is cited anywhere. The S2FC circuit was described in detail in the review of the SS-300-APFC. In essence, it keeps a relatively powerful fan running at extremely low speed until and unless a fairly high load and temperature is reached. After that point, the rate of fan speed change follows an exponential curve so that the maximum RPM / airflow is saved for the highest load. In this way, the PSU runs very quietly under normal and even fairly demanding loads, yet has the full cooling power of the fan when it is needed.

5) Cushion Fan. Rubber grommets are used on the 4 fan mounting screws to reduce noise by lowering the amount of vibration transmitted from the fan to the PSU and through it, to the PC case. Grommets and screws are not as effective as mounts made completely of rubber or other elastomers, however. The grommets are not visible from the outside.

6) Forward Converter. This is a reference to more advanced circuitry that replaces the usual bridge rectifier circuit. I was told it is part of what makes the high 78% / 80% efficiency possible.

7) Doctor Cable. It's a cable management kit consisting of a spiral cable cover made of translucent soft plastic, a handful of zap-straps (locking cable ties) and a large cable mount. The image below from one of the box side panels tells the story. The parts themselves are commonplace in electronics parts stores, but its inclusion in the PSU package is unique. It's practical, generous and well thought out. It makes you wonder why all retail PSUs don't come with something similar!

Warranty coverage is provided for a period of 3 years, which is very generous. Seasonic has implemented an on-line RMA system to expedite service if and when it becomes necessary. The warranty card refers to Full details of the warranty can be seen there.

1 2 3 4 5 Next

Power - Article Index
Help support this site, buy from one of our affiliate retailers!