The Motherboard

The motherboard is the large circuit board inside your computer's case. It's sometimes called the system board, the logic board, the baseboard, or less commonly, the planar board. Everything connected to your computer system, plugs either directly or indirectly into the motherboard.

I'm sure everyone has heard the CPU, or Central Processing Unit, referred to as the 'brain' of your computer. Well, the CPU sits on the motherboard, and if it can be called the brain of your computer then the motherboard is truly the central nervous system. The motherboard contains the CPU, the BIOS ROM chip (Basic Input/Output System), and the CMOS Setup information. It has expansion slots for installing different adapter cards like your video card, sound card, Network Interface Card, and modem. This circuit board provides a connector for the keyboard as well as housing the keyboard controller chip. It has RAM slots for your system's Random Access Memory (SIMMs or DIMMs), and provides the system's chipset, controllers, and underlying circuitry (bus system) to tie everything together.

The motherboard, more or less, is your computer. It defines your computer type, upgradeability, and expansion capability.

Non-Integrated Motherboards
Non-Integrated Motherboards have assemblies such as the I/O Port connectors (serial and parallel ports), hard drive connectors or paddle boards, floppy controllers and connectors, joystick connections, etc. installed as expansion boards. This takes up one or more of the motherboard's expansion slots and reduces the amount of free space inside your computer's case. Hence, the individual motherboard is relatively cheap to produce but, because of the cost of manufacturing, testing, and installing the expansion boards separately, there's an added cost to the computer system. However, if something should go wrong with the individual assemblies, such as a bent or broken pin in a connector, or a defective controller chip etc., you could repair the problem by replacing the individual expansion card at a relatively minor cost.

Most of the older motherboards were Non-Integrated. Some of the later 486 system boards began to integrate some of these assemblies right onto the circuit board.

Integrated Motherboards
Integrated Motherboards have assemblies that are otherwise installed as expansion boards, integrated or built right onto the board. The serial and parallel ports, the IDE and floppy drive, and joystick all connect directly to the motherboard. This is now standard on any late model 486 and above. It tends to free up some space inside the case and allows for better accessibility and air flow. The systems are cheaper to produce because there's less material involved, less installation, and testing can all be done at the same time. They are more expensive to repair because, if you end up with a controller failure or broken pin, it means a new motherboard (and, of course, because of the added assemblies, the motherboard can be more expensive than its non-integrated counterpart). However, these particular integrated assemblies are generally fairly stable and although problems can occur, they tend to be fairly rare.

All in all, the integrated motherboard tends to be a good thing as opposed to the 'Embedded Motherboard'.

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