Q: I was thinking of building a gaming computer and I have been reviewing builds on the internet. Lots of the $750-$1500 and up builds suggest getting a "power supply" box at 550-750 watts. What are they, how do they work, what is the point, and if you know, what are some good ones. Thank you!!!
A: The wall socket you plug your computer into is 120 volts AC (alternating current). The components in your computer run off DC (direct current) of various voltages. The "power supply" in your computer takes the wall current and transforms it into DC current of the correct voltage(s), and feeds this current (via various connectors that come with the power supply) to the components in your computer. Without a power supply, the computer you build will not work. PC power supplies come in various capacities, types and number of connectors, build quality and costs. A poor quality power supply may not deliver the power it advertises, and/or won't deliver power that is within the voltages/current that your PC's components requires. It may even damage your PC. Some power supply brands that have good reputations are Corsair, PC Power & Cooling, and Seasonic (there are others -- those were just examples). As with most products, you generally get what you pay for, though some power supplies are very good values for the money and some are over-priced.