CX400W is the simplest power supply offered by Corsair, featuring active PFC, a 120 mm fan on its bottom, single-rail design and costing only around USD 50. Is it a good product? Let’s see.

Like most power supplies from Corsair, CX400W is manufactured by Seasonic (Corsair HX750W, HX850W and HX1000W are manufactured by CWT). Internally this power supply uses the same design as Corsair VX450W, Antec EarthWatts 500 W and Arctic Cooling Fusion 550RF as we will explain.

Corsair CX400W power supplyFigure 1: Corsair CX400W power supply.

Corsair CX400W power supplyFigure 2: Corsair CX400W power supply.

Corsair CX400W is a small power supply, being 5 ½” (140 mm) deep, using a 120 mm fan on its bottom and featuring active PFC.

Being an entry-level product it doesn’t have a modular cabling system. All cables have a nylon protection that comes from inside the power supply. The included cables are:

  • Main motherboard cable with a 20/24-pin connector.
  • One cable with two ATX12V connectors that together form one EPS12V connector.
  • One auxiliary power cable for video cards with one six-pin connector.
  • Two SATA power cables with three SATA power connectors each.
  • Two peripheral power cables with three standard peripheral power connectors and one floppy disk drive power connector each.

The number of cables is enough for you to build a mainstream PC, and this is the exact same cable configuration found on Corsair VX450W.

All wires are 18 AWG, which is the correct gauge to be used. All cables are very long, measuring 23 5/8” (60 cm) between the power supply and the first connector on the cable, and then 6” (15 cm) between each connector on the cable on cables that have more than one connector. So you can easily install it inside a full tower case.

Corsair CX400W power supplyFigure 3: Cables.

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.