Power Supply Unit Definition Role, Definition, How Works and Types of It
Power Supply Unit (PSU) is the essential key of functioning the rest of the component. Through it, the main AC (Alternating Current) is converted in DC (Direct Current) giving to the rest of the PC parts proper voltages. Motherboard is the mean of delivering the power to the rest of the components except the graphics card which need separate power alimentation. Important manufacturers present on market: Seasonic, Corsair, Antec, Thermaltake, Cooler Master.
PSU Role, How Works
How we said, PSU is the component that converts the alternating current from the wall socket to low-voltage direct current in order to operate the CPU and the peripheral devices. There are some required direct current voltages and must be regulated with accuracy to provide stable operation of the computer.
There are four continuous voltages used by components: +3,3V, +5V, +12V and -12V. All these continuous voltages are converted from AC and delivered to the component that need the specific voltage.
power supply unit – 24 pin connector
Motherboard 24-pin connector
power supply unit – 24 pin connector (mobo)
Motherboard 24-pin slot
Motherboard Connection: it provides power to the motherboard. Nowadays motherboards have 24-pin slot but older ones also have a 20-pin slot. Most power supply allows to convert 24-pin connector into 20-pin by removing the last 4-pin. Motherboards that use 24-pin connector are called ATX12V 2.x and those which use 20-pin connector, ATX12V 1.x.
power supply unit – 8-pin ATX12V
ATX12V 8-pin connector
power supply unit – 8-pin ATX12V (mobo) caption
ATX12V 8-pin slot
ATX12V 8-pin: this connector is used to provide power to CPU mounted on motherboard. In the past, older CPUs have lower TDP (Thermal Design Power) and need only 4-pin connector.
power supply unit – 6-pin or 8-pin PCI-E
PCI-E 6-pin and 8-pin Connector
power supply unit – 6-pin and 8-pin PCI-E GPU
PCI-E 6+2-pin Connector (GPU)
PCI-E 6-pin and 8-pin: those connectors are used to provide power to graphics card in different combination of them. PCI-E 6-pin connector can become a 8-pin, adding extra 2-pin like image above. If a graphics card need more power to function in good parameters, it can have more PCI-E connectors: 1 x 6-pin, 1 x 8-pin, 2 x 6-pin, 1 x 6-pin and 1 x 8-pin, 2 x 8-pin.
power supply unit – SATA Power Connector
SATA Power Connector
power supply unit – SSD SATA Power Plug
SSD SATA Power Plug
SATA Power Connector: This plug is usually used to provide power to storage devices, optical drives and solid-state drives.
power supply unit – Molex Connector
power supply unit – Molex Slot from DVD
Molex Slot from DVD
Molex Connector: It is frequently used to provide power for disk drives.
power supply unit – Floppy Disk Power Connector
Floppy Disk Power Connector
power supply unit – Floppy Disk Power Slot
Floppy Disk Power Connector
Floppy Power Connector: It provides power to Floppy Disk Drive.
Form Factors and Cooling
There are some form factors that not only define physical size of power supply unit but also the type of connectors that it has. ATX12V 2.x and EPS12V being the most popular form factors, there are more older used in the past: Power Supply Unit Definition
– introduced by IBM PC AT in 1984
– delivered four voltages +5V, -5V, +12V, -12V
– use 12-pin motherboard power connector, standard peripheral power connectors (MOLEX) and the floppy disk drive power connector