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SeaSonic S12 430 Watt Power Supply

Power Supply
4th January 2005
Manufacured By
Supplied By


Many people, ourselves included, predicted the massive increase in power supply sales and marketing through 2004 as soon as it became apparent that graphics cards were likely to start requiring significantly more juice than in the past.

Kickstarted by NVIDIA's initial statement that a minimum 480Watt power supply would be required to run their latest high-end GPUs, a specification it later scaled back somewhat to around 350Watts, companies across the globe saw their chance to cash in on a forced upgrade and tempt buyers their way.

With a history in designing and building PC switching power supplies that stretches back to 1975, Sea Sonic Electronics Co. Ltd is actually one of the veterans of this suddenly very visible sector. However, their reluctance to follow the crowds and opt for high gloss titanium coated cases, braided cables, LED fans, modular cable management or any of the other real attention-grabbers means they're not a name that often gets mentioned in the same breath as the likes of Tagan, Enermax, OCZ, Ultra and the like.

Despite its "plain Jane" looks, one of the most stable power supplies we tested last year where voltage fluctuations were concerned, was SeaSonic's SuperTornado, a rather basic 120mm fan-cooled unit that showed no outward signs of the impressive outputs it hid under its casing.

Today we have another, rather mundane looking 120mm fan-cooled unit that, with a relatively lowly 430 Watt rating, isn't likely to activate the drool glands of legions of power users. Badged the "S12", let's see what this new power supply can (or can't) do.

As always, the specs:


Being the 430Watt model, the outputs are listed below under the model S12-430.

Despite a fairly tame 430 Watt total output, the ratings of 30 Amps on both the 3.3V and the 5V lines, and 29A shared between the dual 12V lines are quite generous.

Naturally SeaSonic sing the praises of 120mm cooling, and why wouldn't they? Greater airflow in exchange for slower rotational speeds and reduced noise levels sounds like good reason to sell the idea. The diagram SeaSonic use to demonstrate the advantages (below) is probably a generic one used for the entire range, and as such it's actually a touch pessimistic for the S12 as it shows the fan hitting 70CFM at 2500RPM when in fact the fan fitted in the S12 manages 70CFM at just 1650RPM.


One thing SeaSonic seem most proud of is their best-case 80% efficiency rating. As you can see in this diagram ripped shamelessly from their site, this means as little as 107Watts of power is wasted as heat/unavailable power compared to the other example in the diagram which, in a sneaky little move, shows the kind of efficiency you'd expect only from a non-power factor corrected PSU.

I'm sure I don't need to point out how beneficial this could be to your power bills as well as your PC.

Website Design and Graphics Copyright Wayne Brooker 2004
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