ResearchThe 10-Minute Motherboard Guide
In building a desktop personal computer, the motherboard is the most complicated task. Once you have the board, changing the plugged-in components is as basic as changing batteries, and usually requires no special knowledge. But the motherboard itself will determine everything else that goes into the PC.
It's best if your first experience with a motherboard is with a used one you don't care about. Pull one from an old computer you're throwing out anyway or a cheap used one from the bargain bin at your local PC store. Try to identify the chipset, processor socket, expansion slots, BIOS battery, BIOS chip, and jumper pins. Either get a book on PC repair or look at an online guide for help. Identify what kind of RAM it will take, and how much at the most you could put in. Are the slots for the video card PCI or AGP?
In picking a new motherboard for your PC, you should first know what kind of processor you want to run. A motherboard will generally only support one type of processor, such as a Pentium IV or an AMD Athlon 64. Different central processing units have connectors that vary physically from one another; so don't worry - you can't accidentally plug the wrong processor into the wrong motherboard, at least, not without a hammer (I'm kidding! Hitting your computer with a hammer, while tempting at times, isn't a good idea!). Also, many motherboards will only support up to a certain speed of processor model. In this case, the maximum processor speed allowed would be quoted in the motherboard specifications, either on the box or in the manual.
The slots to plug in RAM is going to be your second biggest concern. You never hear someone say "My computer is too fast! I really wish it would make me wait longer after I click on this icon before the program opens up!" The more RAM you have, the better your machine will perform. Currently there are four main types of RAM memory you can buy for your computer: SDRAM, RDRAM, DDR SDRAM, and DDR2 SDRAM. Without getting into expanding all these ten-dollar acronyms, I have presented them in the order of worst to best. SDRAM is getting old already; don't use it unless you're refurbishing an old motherboard that won't take anything newer. RDRAM is nearly dead and a big hassle to use besides, due to it's awkward setup and proprietary constrictions. DDR (and DDR2) SDRAM is standard and you'll find it everywhere. You want to be able to support at least a Gig of RAM for today's software demands on any platform, and two Gigs if you're going to be gaming, ray-tracing, or compiling. If you're not going to be running Microsoft Windows on a machine, RAM won't be such a concern. But in any case, more slots to upgrade later is always a good feature.
While I mentioned compiling, ray-tracing, or other "power" computer uses, it is unfortunate that a math processor doesn't yet go without saying. So be sure your motherboard and processor setup is capable of dividing 10 by 3 and getting 3.333333333.... Non-power users don't have to worry as much about this, but you should know the difference. The quality of being able to handle precise floating-point operations is known as "integer space" or "precision", and will be a factor if you're hoping that silo rendered in your first-person shooter game you've designed actually looks round. Non-power users (i.e. just Internet and playing games) can save a few bucks getting a cheaper setup without the extra math precision.
Built-in video, sound, USB, and networking are something else you should expect at the very least. As a rule of thumb, I look for the new motherboard I'm buying to have as much capability built in as the motherboard plus all of it's expansion cards together which I'm replacing. This is about right for what you will find, if you upgrade to a new motherboard at the average rate of every five years or so. USB ports are becoming the standard for everything from hooking up peripheral devices (mouse and keyboard, etc.) to storage media; they're even phasing out floppy disks in favor of USB thumb-drives now, so you want ports in front and back of your machine, and at least four of them.
At the rate today's computers advance and become obsolete, a computer of ten years ago measures up to today's computer the same way a model-T Ford measures up to today's Hummer. The insane pace of rapid computer advancement means that you want to buy a machine with nearly unimaginable power if you want it to still be fit to use five years from now.
These specs are aimed at a performance user, including a heavy gamer, anybody doing design work online, or a developer. Refurbishing a used PC for a web server or simple workstation box is a different story, and you can settle for moderately less sophisticated hardware.