THE MOTHER BOARD
Prior to the invention of the microprocessor, a digital computer consisted of multiple PCB's in a case with components connected by a backplane, a set of interconnected sockets.
In very old designs the wires were discrete connections between card connector pins, but PCB's soon became the standard practice. The CPU, memory, and peripherals were housed on individual PCB's, which were plugged into the backplate.
During the late 1980s and 1990s, it became economical to move an increasing number of peripheral functions onto the motherboard. In the late 1980s, personal computer motherboards began to include single ICs capable of supporting a set of low-speed peripherals: keyboard, mouse, floppy disk drive, serial ports, and parallel ports.
- Sockets in which one or more microprocessors may be installed.
- Slots into which the system's main memory is to be installed.
- A chipset which forms an interface between the CPU's front-side bus, main memory, and peripheral buses.
- Non-volatile memory chips containing the system's firmware
- A clock generator which produces the clock signal to synchronize the various components.
- Slots for expansion cards
- Power connectors, which receive electrical power from the power supply and distribute it to the CPU, chipset, main memory, and expansion cards.