Seasonic has just released their 80 Plus Gold power supply line-up, X-Series, which promises 90% efficiency. Let’s take a look at the 650 W model.

As you may be aware, Seasonic is a traditional OEM manufacturer, being the real manufacturer behind units from brands like Antec, Corsair and Arctic Cooling (not all power supplies from these brands are manufactured by Seasonic, though). One annoying thing about Seasonic is that they have three websites,, and, but retail products like the reviewed power supply can only be found on the later. In our opinion this makes no sense and only makes it difficult to consumers to find out more about their products.

Seasonic X-Series 650 W power supplyFigure 1: Seasonic X-Series 650 W power supply.

Seasonic X-Series 650 W power supplyFigure 2: Seasonic X-Series 650 W power supply.

X-Series 650 W isn’t a long power supply, being 6 19/64” (160 mm) deep, using a 120 mm fan on its bottom and featuring active PFC, of course. The fan used on this power supply is from a Japanese brand (Sanyo Denki, even though it was manufactured in the Philippines – welcome to the globalized world) and only rotates when needed. When this power supply is operating at low load and thus relatively cold, the fan does not spin, making this power supply to emit zero acoustic noise under this scenario.

X-series models present a fully modular cabling system, where even the main motherboard cable is modular.

This power supply comes with the following cables:

  • Main motherboard cable with a 20/24-pin connector.
  • One ATX12V cable.
  • Two EPS12V cables.
  • Four cables with one six/eight-pin auxiliary power connector for video cards each.
  • Two cables with three SATA power connectors each.
  • One cable with two SATA power connectors.
  • Two cables with three standard peripheral power connectors.
  • One cable with two standard peripheral power connectors.
  • One adapter for converting one standard peripheral power connector into two floppy disk drive power connectors.

The modular cabling system has five connectors for SATA/peripheral cables, so from the six SATA/peripheral cables that come with the power supply, only five can be used at the same time.

All cables measure 22” (56 cm) from the power supply to the first connector on the cable and on the cables with more than one connector there is 6” (15 cm) between connectors.

All cables use 18 AWG wires, which is the correct gauge to be used.

Seasonic X-Series 650 W power supplyFigure 3: Cables.

The number of cables is more than perfect for a 650 W product.

Now let’s take an in-depth look inside this power supply.


Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.