Computers are rather complicated machines, especially if you've never really had a chance to learn about any of the components that make a computer what it is. The few, very basic, components everyone should understand are the motherboard, the processor (also referred to as the CPU or Central Processing Unit), and the power supply unit (PSU). In this post, I will focus on power supply units.

Your computer's power supply unit is the hardware within your computer that changes alternating current (AC) from a wall socket to low-voltage direct current (DC) to keep the inner components of your computer up and running. When I was building my own computer, which is an HP DC5700, I used the HP 437406-001 Power Supply Unit. So far, I've found this PSU to be incredibly reliable. It puts out 240 watts of power with an input of 100-240 volts AC. It also offers three SATA hard drive connectors, which I've found to be incredibly handy.

The basic features of most modern power supply units include short circuit protection, overload protection, overvoltage protection, over-current protection, and over temperature protection. Along with that, most PSUs will typically always provide your computer with some amount of standby voltage so that the standby functions of your computer and its peripherals can remain powered on. Most power supply units will allow you to remotely start your computer via Wake-on-LAN and Wake-on-ring, as well.

One important factor to consider when looking for a new power supply unit for your computer is its efficiency rating. Modern PSUs have improved immensely in efficiency in recent years, and generally allow for about 70-80 percent energy efficiency. One thing to look out for, though, when shopping for a PSU is that its energy efficiency drops at low loads. Because of this, it is important to match the capacity of a power supply unit to the power needs of the computer you'll be using it in. The PSU I integrated into my computer is about 80 percent energy efficient, and it helps me save a little bit of money on my electricity bill.

Another thing to consider why purchasing a power supply unit for your computer system is going the refurbished route. Refurbished computer hardware offers everything that new hardware offers; it performs at factory standards and is equipped with both a warranty and technical support. The only real difference between refurbished and new is that a refurbished component is much more budget-friendly. Not only that, but it's extremely environmentally-friendly, as well. Refurbished hardware retailers buy old, outdated hardware, refurbish it, and then resell it. This helps to keep an old computer component in working condition and out of a landfill. It's recycling at its best!

When shopping for a power supply unit for your computer, there are a few things to keep in mind: you should make sure the PSU is compatible with your computer, that it will suit your computer's power needs, and that you are getting what you want at a price you can afford. Fulfilling these three factors, like I did when I purchased the HP 437406-001 System Board, will help you get the best PSU for your system possible.