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Computer Hardware

Ministry of Higher EducationBamyan University

Computer Science Department

Presented by : Mustafa Kamel MohammadiEmail : bamian.cs@gmail.com

Motherboard

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Agenda of course Computer hardware

Motherboard PC buses and chipset controllers Microprocessor BIOS, CMOS and boot process RAM and cashe memories HDD (Hard disk) Expansion Cards and system resources Power supply Port and Connectors Monitor and displays

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learning objective In this chapter you will learn

What is motherboard? Components on motherboard Motherboard designs Motherboard form factors

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Motherboard• Motherboard, Mainboard or System board is the main printed circuit board

inside the PC which holds all the following components and connects them with each other.

• Came in many shapes, types and sizes• Motherboard design are different.• Manufacturers attempt to have their own design.

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Components of motherboard• CPU slots and Sockets

• CPU mounts to the motherboard by either a socket or slot

• Chipsets• Device that contains enough circuits to control devices attached to motherboard

• Memory sockets• Place where memory is installed on the motherboard

• BIOS ROM• Small ROM memory that contains BIOS program

• Power connectors• Connections from power supply to other devices are through this.

• I/O connectors• Connectors that allow I/O devices to communicate with CPU

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Components of motherboard• Expansion slots

• Slots where expansion cards are installed on.

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Motherboard designs• Came in two forms • 1 – Motherboard design

• Is the board that integrates all system components of a PC in a single printed board• Environment in which operation flow is implemented.

• 2 – Backplane design• It does not integrates all components• A backbone to connect several printed circuit boards together to make up a complete

computer system• Container board that contains CPU cards, Memory cards , IO cards for adding capability for

system

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Motherboard designs• Passive Backplane boards

• Offer no active bus driving circuitry• Any desired arbitration logic is placed on the daughter cards• Daughter cards are plugged into open slots on the backplane board.

• Processor cards, containing the CPU and its support chips• I/O (input/output) cards, with bus and device interfaces

• Popular on network servers

Cont.

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Motherboard designs• Active backplane boards

• The same as passive backplane boards but Active backplanes include chips which buffer the various signals to the slots.

• The distinction between the active and passive boards isn't always clear.

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Motherboard form factor• Form factor defines a

• Motherboard’s size, shape, and how it is mounted to the case• The size, shape, and function of the system case• The type, placement, and size of the power supply• The system’s power requirements• The location and type of external connectors• The case’s airflow and cooling systems

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Motherboard form factors• IBM PC

• 5 expansion slots• Cassette tape

• IBM PC XT (Extended technology)• 8 expansion slots• Floppy disk drive

• IBM AT (Advanced technology)• First real motherboard standard• Additional circuitry• Bigger size

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Cont.• Baby AT

• Used chipset and controllers to reduce circuitry• Smaller size• Used between 1984-1996

• ATX • All IO connections on the back of PC• Move CPU and RAM nears to Power supply fan and far than expansion slots• Powered ON or /OFF by motherboard signals

• Software control shutdown and start up, notebook start up model

• Mini ATX• Smaller version of ATX, consisting all characteristics of ATX boards

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Data exchange in motherboard• Most of the data exchange takes place on the motherboard itself, where all the

components are connected to each other• Motherboard functions like a central railway station

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Cont.

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References• PC hardware a beginner’s guide by Ron gilster• PC architecture by Michael Karbo