Objectives :

  • List the types of motherboards
  • Identify the- motherboard form factor
  • Identify the components of the motherboard
  • Explain the use of buses
  • Explain the bus architecture
  • List the bus standards
  • Explain the use of chipsets
  • List the types of chipsets
  • Configure the motherboard
  • Install the motherboard
  • Troubleshoot the motherboard

Types of Motherboards :

Integrated motherboards – Have all peripheral device slots, input output ports, serial and parallel ports mounted on the board. Saves space and cheaper as compared to non-integrated motherboards. Disadvantage is that if an individual component of the motherboard fails, the whole board may need to be replaced

Non-Integrated motherboards – Have RAM slots integrated on the board. All the I/O ports such as serial and parallel port connectors, other controllers such as hard drive and floppy disk drives controllers are attached to the system using expansion boards

Desktop Motherboards – Used in personal computers and desktops

Server Motherboards – Designed to offer high-end services and supports various redundant technology

Laptop Motherboards – Have very advanced features, as compared to the desktop motherboards

Form Factors of Motherboard :

Refers to motherboards physical shape, layout and positioning of components on it

Determines the type of system case it will fit into


Obsolete Form Factor :

Types of obsolete form factors :

  • Baby AT – Similar to original IBM XT motherboard structure. It supports a maximum of 8 slots
  • Advanced Technology (AT) – Matches the original IBM AT motherboard in structure and layout Size is very large. It supports a maximum of 7 slots.
  • Low Profile Extended (LPX) – Advantages are low cost and small size. Developed by Western Digital. Difficult to upgrade or expand and exhibit cooling problems. Supports a maximum of 8 slots

Modern Form Factor :

Types of modern form factors :

  • ATX – Popular and has best features of LPX and AT form factors
  • Micro ATX – Limited expandability and capacity
  • Flex ATX – Provides benefits of ATX and micro ATX form factors
  • Mini ITX – Similar to ATX, micro ATX, Flex ATX, and BTX form factors
  • NLX form factors – New addition to motherboard form factors, easier assembly, reduced cost, space efficiency and flexibility

Proprietary Form Factor :

Compaq and HP both use different form factors such as ATX and Micro ATX

Products sold by these companies are of different form factors

Components of a Motherboard :

Motherboard contains slots, sockets and connectors for connecting various devices

Contains super I/O chip, slots for connecting various peripheral devices

Configure the motherboard using jumpers

Connectors :

  • System panel connector
  • USB headers
  • Digital audio connector
  • MDC connector – connects to modem card module
  • Internal audio connectors – conents to CD ROM or voice modem card
  • GAME/MIDI connector
  • System Management Bus (SMBus) connector
  • ATX 12V connector
  • ATX Power Connector
  • CPU and chassis fan connectors
  • Serial Advanced Technology Attachment (SATA) connectors
  • IDE connectors
  • Serial port connector
  • Floppy disk drive connector

On Board Disk Drive Connectors :

Hard drive, floppy drive and CD-ROM drive is connected to motherboard using on-board disk drive connectors

Primary connector used to connect storage devices is the Integrated Development Environment (IDE) port

Serial Advanced Technology Attachment (SATA) technology is used to connect the newer versions of hard drive

Keyboard and Mouse Connector :

Keyboard and mouse device are connected to (Personal System) PS/2 port of computer

Ports are located at the back side of the system

PS/2 port contains 6 holes and a notch in the middle

Power Supply Connector – Types of power connectors used by various power supplies are AT ands ATX power supply connector, ATX auxiliary power connector and ATX 12V connector

Serial and Parallel Port Connector – 9 pin serial port connector and 25 pin parallel port connector are used to connect various I/O devices

Universal Serial Bus (USB) - Offers Plug-and-Play support and also supplies power to the device

Expansion slots :

Motherboard has PCI slots where you can connect PCI cards.

Different PCI cards include LAN card, SCSI card and USB card

Extend the capacity of the existing motherboard

AGP slot is used to attach a graphic card

Audio/Modem Riser :

Card with capabilities of modem and audio

AMR slot is smaller than the standard PCI slot

Now used only for modems


Peripheral Component Interconnect (PCI) Slot :

Bus standard developed by Intel Corporation

Used for attaching peripheral devices to motherboard

Slots work at 33 MHz

newer variants are available that have a 64-bit wide bus and work at 33 MHz or 66 MHz

Data Transmission Rate of PCI is 133 MBps

PCI Extended (PCI-X) :

PCI Extended (PCI-X) is a standard designed jointly by HP, IBM, and Compaq

Increase the performance of high-bandwidth devices, such as Gigabit Ethernet and Fibre Channel

Fully backward compatible with PCI and data transmission rate is 1GBps

Comes in two variants: PCI-X 1.0 and PCI-X 2.0

PCI Express (PCI-E) :

Newest Peripheral Component Interconnect Special Interest Group’s specification for the I/O bus

Extends the capabilities of PCI bus

Having point-to-point, hot-pluggable and hot-swappable system bus

Data Transmission Rate of each lane is 250MBps

AGP Slot :

Accelerated Graphics Port (AGP) is used to display graphics and 3D images in efficient manner

Offers high data transfer speed between the video chipset and the CPU

AGP cards are available at different speeds, AGP 1x, 2x, 4x, 8x

Operate in a voltage of 1.5 to 3.3 volts

Front Side Bus :

Data Bus which carries two-way signal information between the processor and other peripheral and system devices within the computer

Peripherals devices include RAM, graphics processing units, hard disk, expansion cards, and system devices include the BIOS

CPU frequency is set as a multiple of FSB

Jumpers :

Small pins that enable you to configure motherboard settings

Performs different functions when it is shorted and when it is left open, without the shunt

Motherboard manual is a necessity when you deal with jumpers

Motherboards may have jumpers to set the color or mono monitor type, to set the cache memory type and size, to set the processor type, system recovery option and to discharge the CMOS RAM battery

Most of the motherboards currently available in the market have auto jumper setup option

Onboard Components :

  • CPU socket
  • Northbridge
  • Southbridge
  • DDR DIMM sockets
  • Super I/O controller
  • Flash ROM
  • Standby Power LED
  • Audio CODEC
  • LAN controller
  • Mouse port
  • Parallel port
  • LAN port
  • Line In jack
  • Line Out jack
  • Microphone jack
  • USB ports
  • Video port
  • Serial port
  • Keyboard port

Memory Slots :

Provide interface for attaching RAM on motherboard

Maximum number of slots depend on the motherboard

Memory slots are either Single Inline Memory Module (SIMM) or Double Inline Memory Module (DIMM)

SIMMs need to be inserted in pairs but DIMM may be inserted individually

CPU Socket :

Interface that connects CPU with motherboard

Consists of holes in which the pins of the processor are installed

Sockets are used with particular type of processor

Sockets already installed on board

Most of the sockets used are built on the Pin Grid Area (PGA) architecture

CMOS Battery :

Complementary Metal Oxide Semiconductor (CMOS) batteries power CMOS chip of motherboard

Saves settings and time when computer is switched off

Last for around 5 years but it depends mainly on the environment in which it is used

Mostly made up of Lithium


Contains necessary code required to operate basic system utilities such as the display device, keyboard or disk drives

Built into Read Only Memory (ROM) of computer

Provides the basic input output functionality of the system

POST is the test conducted by BIOS

Super I/O Chip :

Single chip similar to system chipset

Controls I/O functions of motherboard

Smaller, slower speed devices are controlled by this chip such as floppy drive, serial ports, PS/2 mouse, some keyboard functions and parallel ports

Supports Enhanced Parallel Port (EPP) and the Extended Capabilities Port (ECP) technology

CPU Voltage Regulator :

Regulates voltage supplied over a line

Protects devices from power surges and spikes

Installed on motherboard and regulates voltage that is needed by CPU

It is a DC to DC converter

Senses voltage needed by processors from the processor itself

Senses Voltage Identification (VID) from processor and supplies the voltage accordingly

Bus Architecture :

Paths through which data is transferred between devices and components

Classified into two main categories :

  • System bus
  • I/O buses

System Bus - Connects the CPU, RAM and the optional buffer memory (cache)

I/O buses – Connects the CPU with other devices such as the peripheral devices

System bus is located on the CPU and other I/O buses branch out from the system bus

In new systems, the system bus is also called the Front Side Bus (FSB)

Bus Standards :

Different types of I/O buses that transfer data across components of the system

Common bus standards are :

  • Video Electronics Standards Association (VESA) Local Bus - It is a 32-bit bus that runs at a speed of 33 MHz. VLB was introduced to address video problems in personal computers. It is no longer used and has been largely replaced by the PCI bus
  • Peripheral Component Interconnect (PCI) Local Bus - Is the most popular I/O bus. Some PCI buses have a width of 64 bits. Provides better performance. Has separate circuitry that controls it. PCI generally supports 3 or 4 slots. You can connect video cards, SCSI host adapters and network cards to the PCI expansion slot
  • Accelerated Graphics Port (AGP) bus - Provides high performance graphics capabilities to the system. This bus forms a dedicated path between chipset and graphics subsystem which enables creation of 3D graphics
  • Industrial Standard Architecture (ISA) bus - Has a bus width of 8 or 16 bits and obsolete
  • Extended Industrial Standard Architecture (EISA) bus - Has a bus width of 32 bits and is compatible with ISA cards and obsolete
  • Micro Channel Architecture (MCA) bus – Created by IBM and had a bus width of 16 or 32 bits and obsolete

Chipsets :

Leading manufacturers are

  • Intel, AMD, VIA, and SiS

The Intel 915, 945 and the 975 chipsets are the most common chipsets available today. 64 bit computing technology chipsets are also available today

Modern chipset consists of the Northbridge and the Southbridge

The chipset controls the data transfers between every component of the system

So the chipset that you choose must support the interface required by your CPU

Factors for selecting a Motherboard :

Form Factor – Defines size and shape of board. While choosing a motherboard, you need to consider the different types of slots you require for your system. Choose a case that is large enough to fit the motherboard of the correct form factor

CPU Support – Should support different types of microprocessor and sockets. Before purchasing a motherboard, you need to consider the various processors that it supports. In the future, if you need to upgrade your processor, you may not have to change the whole motherboard

Memory slots – Should have more number of slots. To support new technology software user can upgrade the system in the future

Expansion Slots – A motherboard with more number of expansion slots can easily be expanded for supporting the various devices

SATA support – Allows higher transfer rates of data between hard disk and motherboard and should have SATA controller on it.

Number of Ports – Should have more number of USB and other ports to connect different devices to the system. Depending on the type of device to be attached to the system and the port that is required, the board should be purchased.

Hard Drive transfer speed and RAID support – Should support Hard drive of Ultra Direct Memory Access (UDMA) 133 and RAID

Bus Speed – Should have higher speed of FSB and BSB which allows faster transfer rate of data in and out of the processor

Chipset – Backbone of system and important part. Should support latest memory modules e.g. DDR II SDRAM, RDRAM or ECC memory. Also it should support AGP 4x or faster video and ATA-133 or faster hard drive support

#Motherboards #Types_of_Motherboards #Form_Factors_of_Motherboard #Obsolete_Form_Factor #Modern_Form_Factor #Proprietary_Form_Factor #Components_of_a_Motherboard #On_Board_Disk_Drive_Connectors #Keyboard_and_Mouse_Connector #Expansion_slots #Audio/Modem_Riser #PCI_Slot #PCI-X #PCI-E #AGP_Slot #Front_Side_Bus #Jumpers #Motherboard_Onboard_Components #Memory_Slots #CPU_Socket #CMOS_Battery #BIOS,Super_I/O_Chip #CPU_Voltage_Regulator #Bus_Architecture #Bus_Standards #Chipsets #Factors_for_selecting_a_Motherboard