Powering Your PC: Truths and Misconceptions
A Guide To Power Supplies

Conclusion:

I hope this guide has been an informative source and shed some light on the deep dark secrets of power supplies. Hopefully this article will continue to grow and be refined over time, providing more useful information to the masses.

The complexity and function of a PC power supply makes choosing a brand / model a very important and tough decision. High-end video cards (especially in SLI setups) require a lot of current and stable voltages to operate properly. Many video cards are starting to use a dedicated power plug for additional 12V current. Processors also require a lot of current, and with dual-core chips appearing power consumption took a noticeable jump.

Always, always, always, before buying a power supply check the manufacturer's warranty and the store's return policy, so if something happens or you decide you don't like it then you can RMA or return the power supply.

Further Reading:

I have written another article that further discusses PC power supplies, and also explains our Testing Methodology @ EXTREME Overclocking. The article covers such topics as ATX12V specification differences, Manufactures & OEMs, SLI / dual video card considerations, how we measure & compare, voltage regulation, efficiency, safety, and of course a compiled list of test results and connector wirings. It is definitely worth reading!

Credits:

Here is a list of sources that were cited in this article. They are excellent reading and provide additional insight, so if you have some free time or are looking for more technical information then read up!

¹ Introduction to Power Supplies (November 1988), Ralph E. Locher - National Semiconductor
² Switching vs. linear power supplies (July 1, 1997), Paul Watkin
³ Special Function Filters (May 16, 2005), Rob Howald
⁴ Watts and Volt-Amps: Powerful Confusion (2003), American Power Conversion
⁵ ATX 12V v2.01 Power Supply Design Guide (2004) Intel Corporation