Seasonic X Series: X-750 Power Supply Review

Fully modular, 750 watts of computing power, high efficiency, and a great build quality has been done before in the world of PSUs, but never quite like this. Seasonic's X Series is an evolution in the world of power supplies.


In the power supply realm when consumers think of quiet and efficient power supplies one of the first company that comes to mind is Seasonic and today we have our third crack at a Seasonic branded unit. This review marks the launch of Seasonic’s newest line of power supplies the X series with the unit we have here today being the X-750 (SS-750KM).

Seasonic is one of the older companies producing consumer power supplies having been founded in 1975 and entering the PC power supply production market in 1980. During that more than 30 years as a company Seasonic has cultivated lines of power supplies that are today some of the standard bearers for efficiency and quiet computing. This focus, and their reputation for quality, has lead to a real explosion in production as Seasonic can be found providing OEM services on various model lines for Antec, Corsair, PC Power and Cooling, and of course under its own Seasonic brand.

Article Image

X Marks the Spot

The Seasonic X-750 is the third Seasonic power supply we have seen under Seasonic’s own label. It is, however, not the first 750W Seasonic unit we have seen as the PC Power & Cooling Silencer 750 Quad CrossFire was an off the shelf x900 rated at 750W's. That unit, however, came out some time ago and was a much more traditional design. Since then, Seasonic has moved on to DC-DC VRM based designs with the first one being the M12D, which was also excellent. Today, we have the opportunity to see Seasonic’s second shot at a DC-DC design in the revolutionary new design that is the X-750. Seasonic was seemingly not content to simply refresh their previous DC-DC design and instead went all out in its second DC-DC design under their own brand as we see from the marketing with this unit:

Sea Sonic Electronics Co., Ltd. today announces the release of the company’s flagship "X" series power supplies, the world’s first ever 80PLUSآ® Gold certified, full modular, multi-output ATX standard power supplies for general sales.

The "X" series, available in 650 & 750 watts output power, showcases the advancement in power supply design technology and embedded inside each unit are two (2) patented features to make the "X" series the most advanced PC power supply on the market today.

Seasonic Patented DC Connector Module with integrated VRM (Voltage Regulation Module) . This patented feature takes the concept of modularity one step further and provides not only complete modular system integration flexibility but at the same time, reduces the current transfer between the PSU main PCB which means enhanced power utilization efficiency, output stability, safety and security.

Hybrid Silent Fan Control2. This patented features upgrades the current Seasonic market leading S2FC (Smart & Silent Fan Control) design with three (3) separate operating modes, fanless, silent and cooling. This unique fan control circuit in combination with the world leading Sanyo Denki San Ace PWM (Pulse Width Modulation) shaped blade, ball bearing fan, makes the "X" series the leader in power supply silence and cooling technology.

In addition, the "X" series power supplies utilizes the highest quality level of material usage such as solid polymer capacitors, high grade and high temperature electrolytic capacitors, dual sided PCB and even scratch resistant power supply case coating, all to make the Seasonic "X" series, the highest standard power supply available in the market today.

The "X" Series is the crowning achievement of Sea Sonic Electronics’ 34 years of dedication to power supply research, design and production and the continued pursuit of ideas and purpose to better the environment and achieve our slogan, Green Innovation Powers Your Life.

Now that we know what Seasonic expects from this power supply let’s see what we have to look forward to when we purchase the X-750 in terms of documentation, accessories, cable count, rail layout, output characteristics, and general build quality.