A motherboard is the underlying circuit board of a computer. The central processing unit (CPU), Random Access Memory (RAM), hard drive(s), disk drives and optical drives are all plugged into interfaces on the motherboard. A video interface and sound card can be optionally built-in or added.

A motherboard can come in many configurations to fit different needs and budgets. At its most basic, it comes with several interfaces for necessary components and a BIOS chip set to control setup of the motherboard. Many computer enthusiasts favor one type of BIOS over another and will choose a motherboard partially based on the BIOS manufacturer. For example, many gamers prefer the Nvidia BIOS as it is rated as one of the best for graphics applications.

An equally important feature of the motherboard is the type of CPU it will support. Some motherboards support AMD CPUs, while others support Intel processors. Within the manufacturer's categories, there are different grades of CPUs. An AMD 64-bit processor requires a different CPU socket than an AMD 32-bit processor. Thus, if purchasing parts independently, one must decide on the CPU before choosing the motherboard to ensure compatibility.

Another important consideration is the amount and type of RAM the motherboard will support. It is always best to buy a board that supports more RAM than currently needed. If new technology for RAM chips is available, getting a board that supports the newer chips will help future-proof the investment.

The number of PCI slots varies from motherboard to motherboard, as do other interfaces like the number of SATA ports, differing RAID abilities, and USB and Firewire ports. As mentioned prior, sound and video capability might be built-in, though purists generally prefer to disable internal video and sound and add superior third party cards. A motherboard also comes in one of a few standard footprints or sizes. This figures in when purchasing the system case. Along these lines, many motherboard manufacturers recommend particular power supplies that have been tested with the board.

Though building a computer used to be somewhat challenging, today most motherboards are color-coded with controllers built-in, making it very easy to build a computer from scratch. The only time consuming aspect is investigating which hardware will best suit your needs while fitting into your budget. Once the CPU and motherboard is chosen, RAM is somewhat determined by the board itself. Hard drives, an optical disk, a video card, a sound card and a floppy round out the basics.

There are many technical websites that review new products. If you are in the market for a motherboard, you might want to spend some time researching your choices. A good motherboard will be easy to set up, will support all of the hardware you desire, and will serve your needs into the foreseeable future. A motherboard that supports the newest technology available will be more expensive than boards that are already close to obsolete.

Often older motherboards are blown out at reduced prices, complete with a CPU, and in some instances a case with power supply. These "barebones" systems are meant to be built from that point up with other components of your choosing. Though you can get a good deal on such a system, in some cases the motherboard included does not support one or more newer technologies, and therefore lacks the flexibility or longevity of a more current model. Therefore, be sure the system supports all of the technologies you desire before making a purchase.