Mother Board and Buses. By Tony Jia 2010.02.19. What is a Mother Board?.
By Tony Jia
Motherboards have come a long way in the last twenty years. The first motherboards held very few actual components. The first IBM PC motherboard had only a processor and card slots. Users plugged components like floppy drive controllers and memory into the slots. Today, motherboards typically boast a wide variety of built-in features, and they directly affect a computer\'s capabilities and potential for upgrades.
A typical desktop computer has its CPU, main memory, and other essential components on the motherboard. Other components such as external storage, controllers for video display and sound, and peripheral devices may be attached to the motherboard as plug-in cards or via cables, although in modern computers it is increasingly common to integrate some of these peripherals into the motherboard itself.
These paths are called "buses."
A bus is simply a circuit that connects one part of the motherboard to another. The more data a bus can handle at one time, the faster it allows information to travel. The speed of the bus, measured in megahertz (MHz), refers to how much data can move across the bus simultaneously.
The more buses that connect to a component, the faster it can operate. Buses work just like highways. Wider highways and highways with more lanes are able to carry more traffic than smaller highways and highways with less lanes. The width of the bus determines the number of bits that can be sent simultaneously. In other words, the wider the bus, the faster the computer. A one-byte bus is composed of eight lines. This means that eight bits can travel down the line at one time. A thirty-two bit bus can send four bytes at a time.
Many cities have a freeway. A freeway is designed so that large amounts of traffic can move quickly from one place to another. The motherboard also has a "freeway." It is called the "front side bus," (or FSB). It is the most important bus on the motherboard, because it connects the processor to the main memory and the Northbridge chipset. The faster the FSB is, the faster the computer can operate, since the processor is constantly using the main memory to store and retrieve information. Sometimes the FSB is also called the "system bus.“
The Chipset, (2 chips on this motherboard) is like a traffic police, manages and directs the flow of data between each of the components. The BIOS is where the computer\'s settings are stored and changed. In this picture, you can see most of the connecting slots, ports, and connectors.