Everything You Need to Know About Power Supplies
 

In this tutorial we will explain about everything you need to know about PC power supplies, including form factors, efficiency, power factor correction (PFC), rails, protections, ripple and much more. You will learn that the power supply power rating should not be the only factor to consider when buying a power supply unit.

http://www.hardwaresecrets.com/article/181

Also read: http://www.madshrimps.be/?action=gethowto&howtoID=77
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