The power supply allows all the components of the PC to operate, by providing them with the necessary power. It converts the 220V AC voltage into DC voltage 12V.
They can be of different power ratings from 250W to over 1500W power supplies for the most demanding.
There are different types, but most common is the ATX standard, common to all desktops.
One can distinguish several types of catches of the devices to power :
- The 24 pin socket used to power the motherboard. It is easily recognizable because it is the largest.
- The plug COM. It powers the side of the motherboard.
- Molex plugs. They can be numerous (between 4 and 10) and used to power various devices. (HDD, optical drives, etc. ...)
- The SATA which are gradually replacing the Molex.
- The plugs PCI-Express 6 and 8 pins that supplies the graphics devices.
Modern power supplies are modular and powerful, that is to say that one can add or remove power cables in an aesthetic concern, but also to balance the voltages on the various power rails.
They can also be certified by the standard 80 + (bronze, silver, gold). This standard aims to promote the power with an electrical efficiency greater than 80%.