Computer Power Supply Tutorial |
The power supply (power supply unit or PSU) is a rectangular box with several cables that fits in the top back of the case. Its primary purpose is converting AC power from an outlet to DC power the computer can use. The cables have connectors on the ends which supply different voltages to various internal components with the main connector plugging into the motherboard. However some, called modular power supplies, contain built-in connectors so you can use only the cables that are necessary.
Power supplies conform to the ATX factor and come in a range of different wattages - from less than 300W to more than a 1000W. Which should you buy? Depends on what type of system you have. For the average system with one or two hard drives, a DVD drive, dual core CPU, and a low-end graphics card, I would suggest at least a 500W PSU. If you plan on adding more drives, get a unit that can handle the job. Better yet, go ahead and buy a 600 or 700 watt just in case upgrading is in your future. Very powerful machines such as gaming systems can use power supplies that are 1000W or more. Motherboards designed for SLI or Crossfire have PSUs specifically made for them. After purchasing, make sure the voltage is set to the correct number by using the voltage selector (100-120V for N. America. & 220-240V for Europe). Thermal Take, Cool Max, and Cooler Master are just some of the major manufacturers of PSUs.