The S12 series doesn’t sport flashy LEDs or a highly reflective chrome finish. The paint job on the S12 is an industrial looking black powder coat finish. As the name implies, the S12 has a 12cm (120mm) fan that keeps the unit nice and cool. The fan is located on the bottom side of the PSU and draws air into the unit. At the back of the unit is a “honeycomb” grill that provides very good ventilation. This allows the hot air to be pushed out of the unit easily.
The Seasonic S12 330W has plenty of power connectors and also features Serial ATA power connectors. The unit has one main power connector, one ATX12V, five 4-pin molex connectors, and two Serial ATA connectors. Each of the cables, excluding the main power connector, is twisted. Twisted cables make it much easier to organize cables and reduce clutter. The main power connector unfortunately is not sleeved or braided, but Seasonic has included a cable management kit called “Dr. Cable.” In the package, they include a cable mount, cable ties, and a split tube, which wraps around the main power connector and acts as a sleeving for it. Another nice feature on this unit is the Easy Swap Connector found on the 4-pin molex connector. The easy swap connectors make the molex connectors easier to remove, as the grip is larger and squeezing the connector helps to loosen it.
One of the main features of the S12 is its high efficiency. Seasonic’s Super series featured an efficiency of up to 78% while the industry average is around 68%. With the release of the S12 series, Seasonic raised the bar to 80% efficiency. While this 10-12% difference may seem really small and insignificant, it makes a large difference when it comes to heat output and thus the amount of active cooling required is reduced. The below diagram taken from the Seasonic website shows the difference in heat output of an 80% efficient power supply and a 68% efficient power supply.
The heat output at 80% efficiency is almost half of the heat produced at 68% efficiency. This helps greatly in reducing the amount of noise provided by the unit, as the fan doesn’t need to spin very fast. Seasonic’s S12 also features Active PFC that helps to reduce the amount of power lost during conversion from AC to DC. Now that we have finished examining the features offered by this unit, let’s take a peek inside the unit itself. After removing the screws from the unit, we removed the cover to reveal the insides of the unit. There are two prominent heatsinks in the unit which will provide good cooling and also all of the components are large and of high quality. The weight of the unit also assured us that this was indeed an excellent power supply. Seasonic power supplies are known for their silence, so we decided to take a listen to it while nothing else was running. When we turned it on it was barely audible. All we could hear was the very faint noise of air moving around. We were very impressed by the sound levels of this unit and compared to the Ultra X-Finity from a few weeks ago, it’s pretty much silent.