One of the most important and least understood parts of an electronics project is the selection of the proper power supply. Power supplies are available in a wide range of sized and specifications and this can make the task daunting. Most basic power supplies accept a fixed input voltage and convert that to a different voltage at a specified current. Computer power supplies provide a set of voltages that are used to power the motherboard and a wide array of peripheral equipment.

Here are some important points to consider when you are buying power supplies for you electronic projects:

• Be certain that the power supply you select can support the expect load. You should be fairly generous when deciding on the load capacity and always specify at least a 20% overhead in load.
• You should consider cooling for your power supplies. They generate a great deal of heat and can quickly fail or cause the failure of other components if they are allowed to run hot. Many computer power supplies include integrated fans to provide cooling, but depending on your project you might consider additional case fan.
• Consider the need for expansion peripherals and be certain you have extra connection points in addition of the load overhead. Otherwise you will have to change out the power supply as your project grows.
• Keep in mind that size, dimension and weight play a role in the overall design of your project. Place close attention to the package size of the power supply so you will be certain it fits in your project.
• Power supplies vary in price and quality. You can find low end power supplies for around $30 while very high end server power supplies can cost as much as $150.

There are many online retailers who specialize in power supplies. They can normally help you find just the right one for your project.