Description
What To Look For
Recommendations

Already know what a Motherboard is and what to look for? Then skip to the Recommendations. 

What To Look For:

• There are many parts of the motherboard to consider. I'll start with the bus speed support. The fastest pentium IV CPUs run at 800 MHz bus speed, and the fastest Athlon XP CPUs run at 400 MHz bus speed (both of these are in actuality 200 MHz multiplied 2 or 4 times by being double or quad pumped).
• The type of Chipset is the most important thing to consider in your motherboard. The chipset contains all of the motherboard's basic instructions, and also determines many of the motherboard's features.  Latest chipset info is available under Motherboard Recommendations.
• Hardware support is also quite important as you want your motherboard to support the hardware you are putting in it. Most of this will be determined by the chipset, but some will not, such as number of slots for memory expansion, number of PCI slots, number of USB and Firewire ports, and the presence of LAN, audio, and other possible onboard components. USB 2.0 and Firewire connectors come in handy for connecting peripherals.
• Onboard components used to be something to avoid, but they have improved lately. Getting an onboard network connector is usually helpful, and onboard audio is common now too.  Onboard video is generally something to avoid though. Onboard audio generally isn't going to give you the best quality, but it's sufficient in most cases. With the nForce line of motherboards, the onboard audio is excellent. 
• Another thing to consider is whether the motherboard comes with a cooling fan on the chipset.  As speeds increase and chipsets become more complex, having good cooling becomes more important.  While this isn't one of the most important things to consider, it is another sign of a good motherboard.

Buying Tips:

• There aren't many buying tips to be concerned with as most motherboards have fairly similar costs.  The motherboard cost is often determined by the chipset being used.  Obviously, you will want to get a motherboard that is going to last you awhile though. One key to doing this is to be sure your motherboard will support the newest CPUs.  Of course, it's not always wise to buy the first motherboard based on a new chipset either. So, this decision can be a tough one...  Often times it is best to wait a little while after a new chipset has come out to be sure the new products are good quality. 

More Info:
Description
Recommendations