How-to Guide: Index

Power Supply Units (PSU)

Overview to Power Supply Units for computers and telecommunication devices. Especially you will find here informations to:

  • ATX PSU's
  • Laptop PSU's
  • Monitor PSU's
  • PSU's for DSL- and LTE modems

ATX Power Supply Units

The ATX form factor is a technical standard that standardizes the dimensions for power supplies, motherboards and expansion cards. 

The standard dimensions WxHxD = 15x8, 6x14cm. At higher powers, the depth value is often greater than 14cm. 

In addition to the ATX form factor is in addition to consider when choosing: 

Performance of the power supply 
different plug design in ATX1.0-2.1 and ATX2.2 
Availability of the required connections for the power supply of peripheral devices such as hard disks, drives, fans over SATA, Molex and other interfaces 
is a PSU with on / off switch needed? 
A 230V Asugang needed, such as for a monitor? 
fits the arrangement of 230V sockets and I / O switch on the back with the cutout in the back panel of the PC match? 


Notebook Adapters

As a standard for many notebooks a voltage of 19Volt has established. These power supplies are available in various power levels of about 2.4A to 4A. The selection should be at least the power demand of the notebook correspond to avoid overloading the power supply and malfunctioning of the laptop. Usually notebook power supplies today are equipped on the secondary side with round connectors. Typical diameters are 5mm, 5.5mm, 6mm. 

There are also universal power supplies, which are accompanied with different adapter plug versions. If necessary, the voltage can be preset. You must always match the voltage indicated on the nameplate of the notebook. In circular connectors must be observed in the use of universal power supplies, whether positive or negative pole is applied externally. 

Monitor power supplies 

This applies largely the same as for Notebook Power Adapter. Most here, however, a voltage of 12V is used. 

AC adapters for broadband and LTE modems 

Broadband and LTE modems are usually powered by small plug power supplies with the required operating voltage. This is usually at 5V or 12V at a current of up to 1.5 A.