Choosing a Motherboard

"You can't choose your mother, but you can choose your motherboard."

-- Some moron who thought he was funny

There are a wide variety of motherboards available today. When selecting a new mobo for your homebuilt computer, many things have to be taken into consideration, including:

Form Factor. The form factor is a set of standards that include the size and shape of the board, the arrangement of the mounting holes, the power interface, and the type and placement of ports and connectors. Generally, you should choose the case to fit the mobo, not vice-versa. But if there is a case that you simply must use (either because it's the one you happen to have or because you really, really like that case), then make sure the motherboard you choose is of a compatible form factor.
Processor support. You must select a mobo that supports the type and speed of processor you want to use and has the correct type of socket for that processor.
RAM support. Make sure that the motherboard you select supports enough RAM of the type (DDR-SDRAM, DDR2-SDRAM, RDRAM, etc.) that you want to use. Most motherboards manufactured as of this writing can support at least 4 Gig of RAM, with DDR2 being the most popular type because of its speed and relatively low cost. Most DDR motherboards also support dual channel DDR, which can further improve performance. But to take advantage of dual-channel, the RAM sticks must be installed in matched pairs, and the mobo must support it.
Chipset. The chipset pretty much runs the show on the motherboard, and some chipsets are better than others. The chipset cannot be replaced, so the only way to solve problems caused by a bad chipset is to replace the mobo. Read the reviews of other motherboards using the same chipset as the one you are considering to see if a lot of people have reported problems with it.
SATA support. There's really very little reason not to use SATA drives these days. They're priced comparably to EIDE drives, but deliver much higher data transfer. But to use SATA, your motherboard must have SATA support. (Well, you can actually install aftermarket SATA expansion cards, but why do that on a new computer?)
Expansion Slots and Ports. How many of each type of expansion slot are included? Will they be enough to meet your current and future needs? How about Firewire support? And does it have enough USB slots for all the peripherals you want to dangle off of it?
Reputation. Search the newsgroups to see if others have found the board you are considering to be a lemon. One excellent Web resource for motherboard research is Motherboards.org. When choosing a motherboard, reliability is the most important factor. Replacing a failed motherboard requires essentially disassembling the entire computer, and may also require reinstalling the operating system and applications from scratch.
Compatibility. Most motherboards include drivers for all recent Windows versions, but check the documentation just to be sure. If you plan to use the board for a computer running another operating system (Linux, UNIX, BSD, etc.) first check the with the motherboard manufacturer to see if it is compatible, and then search the hardware newsgroups for the OS you will be using to see how that particular board has worked out for others.
On-Board Features. Do you want integrated audio or video? If you don't plan on using the computer for graphics, multimedia, or gaming, then you may be able to save money by buying a motherboard with less-than-spectacular integrated audio and/or video.
RAID Support. RAID (Redundant Array of Independent Disks) is a set of protocols for arranging multiple hard drives into "arrays" to provide fault tolerance and/or increase the speed of data access from the hard drives. Many motherboards have RAID controllers built-in, saving you the cost of installing an add-on RAID controller.
Cost. Even if you are on a budget, the motherboard is not the place to cut corners. Try a less fancy case, instead. A good motherboard is more important than neon lights. But at the same time, the fact that one mobo costs twice as much as another doesn't mean it is twice as good. By searching newsgroups and reading hardware reviews, you're likely to find some inexpensive boards that perform as well as (or even better than) boards costing a great deal more.

For a list of motherboard newsgroups and other helpful resources, check out the links page.

Getting Started

Components
- Motherboards
  - The Motherboard
  - Expansion Interfaces
  - Choosing a Motherboard (This page)