Motherboards

Parts of a motherboard

Motherboards connect the diverse elements of a PC, enabling them to communicate with one another and work together.

Motherboards have easily identifiable slots designed to fit the various PC components that need to communicate, indicating the CPU, memory, hard drive, and video card. Each component slot is easily identifiable.

Motherboards have external ports that enable input devices such as mice and keyboards to communicate with the system.

CPU socket/slot Slotted – older Athlon, Celeron Socketed – current Pentium 4, Athlon XP, Dual Cores

CPU fan connector Small three- or four-wire power connector Plugging incorrectly will cook the fan or short the power

connector Memory slots

ATX – have two to four black slots Also DIMM or RIMM slots

Power connector - P1 power connector only powers the CPU and memory

EIDE and FDD ports Enhanced Integrated Drive Electronics Floppy Disk Drive EIDE – 40 pins FDD – 34 pins

Chipset Two chips: Northbridge and Southbridge Northbridge – helps CPU work with RAM Southbridge – handles expansion devices and mass storage VIA Technologies (brand)

Expansion slots (AGP, PCI, CNR) Accelerated Graphics Port – for 32bit, 66-MHz connections for

video cards Peripheral Component Interconnect – general purpose, 33-MHz

slots Communications and Networking Riser – for Internet and small

network connections

Date and Time Battery Enables system to reatin accurate date and time settings

Flash ROM BIOS (Basic Input Output System) – a small set of code that

enables the CPU to communicate properly with the devices built into the motherboard.

AMI, Award BIOS and Phoenix (brand) Front Panel Connectors

Power and reset buttons, power and hard drive activity lights and the tiny speaker.

Jumpers and DIP switches Jumper – a pair of wires that you enable or disable by

placing a small plastic and metal shunt over both wires. DIP switch – a little plastic box, often blue, with tiny

switches.

External Ports PS/2 – two small round ports on the edge closest to the

CPU mini-DIN ports Green – mouse plug , purple – keyboard plug

Parallel and serial ports Parallel – 25-pin, D-shaped female port (printer and scanner) Serial – 9-pin, male port (mouse)

USB (Universal Serial Bus) – enables you to connect up to 127 different devices at the same time

Network Port – Internet connection via a standard RJ-45 port

Sound and Game Ports Green (speaker), pink (microphone), blue (line-in) Game port – 15-pin, two row, female, D-shaped port

Types of Motherboard

The ATX mother board is the most common motherboard form factor

The ATX form factor was developed from the earlier AT form factor. AT motherboards were original motherboards for PC system.

Baby AT motherboards were smaller, but did not solve the problematic issues with the AT design.

Form Factors

The form factor usually defines a motherboard's size, shape and how it is mounted to the case, but now includes: size, shape and function of the system case type, placement and size of the power supply system power requirements location and type of external connectors case airflow and cooling systems.

A backplane is a circuit board into which other circuit boards can be plugged.

AT Old-style computer motherboard Invented by IBM Large keyboard plug (DIN connector), split P8/P9 style

power socket Baby AT

Smaller AT version ATX

Standard motherboard form factor at present time MicroATX

Smaller version of ATX Less expensive

FlexATX Created by Intel, 1999 9x7.5 inches dimension For lowest cost computers

AT motherboard

Baby AT above AT

AT and ATX

microATX

Install a motherboard in a system Installing a motherboard requires four things:

Research, preparation, common sense and patience Make certain that you have the proper case for you motherboard

form factor, antistatic protection, and the standout screws and standard screws ready and waiting.

Use common sense: don’t force something if it doesn’t seem to want to go in easily. Be patient and through; check and double check your connections to make certain that they line up, and that you have the parts oriented properly.

It is often easier on the tech and the motherboard to install the CPU, CPU fan, and RAM on a motherboard before installing the motherboard in the case.

Review Questions

1. The original form factor for a PC motherboard was the .

a) ATb) Baby ATc) ATXd) LBX

Review Questions

2. Which external port is usually used for printers?

a) Serialb) Parallel c) Game d) Print

Review Questions

3. Which port allows simultaneous connection of up to 127 devices?

a) USBb) Parallel c) Seriald) Game

Review Questions

4. Which port on the motherboard provides a standardized interface for hard drives?

a) FFDb) AGPc) PCId) EIDE

Review Questions

5. What portion of the motherboard connects to the power supply?

a) P8/P9 power connectorb) P1 power connectorc) P4 power connectord) P1/P2 power connector

Review Questions

6. What portions of a motherboard can enable or disable some built-in devices?

a) Jump switches b) Serial switches c) Jumpersd) Parallel switches

Review Questions

7. What is the generic name for DIMM slots and RIMM slots?

a) Memory slotsb) AGP slotsc) PCI slotsd) P8/P9 slots

Review Questions

8. What is the name of the keyboard connector on an AT motherboard?

a) Flexb) PS/2c) P8d) DIN