A motherboard is the main circuit board in a computer that connects the central processing unit and RAM to other components like expansion cards and ports. It contains chipsets to interface with peripherals and components like the CPU socket, memory slots, expansion slots for graphics and other cards, and front panel connectors. Key factors in motherboards include the form factor like ATX or Mini-ITX and components like the northbridge and southbridge chips that connect different parts of the system.

1. Motherboard
A motherboard (sometimes alternatively known as
the mainboard, system board, baseboard, planar board
or logic board, or colloquially, a mobo) is the main
printed circuit board (PCB) found in general purpose
microcomputers and other expandable systems.

2. System Board Factors
 Advanced Technology Extended (ATX)
 Micro ATX
 Information Technology Extended (ITX )
 Mini-ITX
 Nano-ITX
 Pico-ITX
 Mobile-ITX

3. System Board Components
■Chipsets
■ Expansion slots and buses
■ Memory slots and external
cache
■ CPUs and their sockets
■ Power connectors
■ Onboard disk drive
connectors
■ Keyboard connectors
■ Integrated peripheral ports
and headers
■ BIOS/firmware
■ CMOS battery
■ Jumpers and DIP switches
■ Front-panel connectors

4. Chipsets
A chipset is a collection of chips or circuits that
perform interface and peripheral functions
for the processor.

5. Northbridge and Southbridge

6. Expansion slot is a connection or port located inside a computer on
the motherboard or riser board that allows a computer hardware expansion card to
be connected.
Expansion Slots

7. Types of Expansion Slots
• Peripheral Component Interconnect (PCI)
Network card, SCSI, Sound card, Video card.
• Accelerated Graphics Port (AGP)
Video card.
• Peripheral Component Interconnect Extended( PCI-X)
• Peripheral Component Interconnect Express (PCI e)
Video card, Modem, Sound Card, Network Card.
• Communications and networking riser (CNR)
• Modem, Network card, Sound card.

8. Power Connectors
Power Connectors a special connector (the 20-pin block connector shown in
allows the motherboard to be connected to the power supply to receive
power.

9. Front-Panel Connectors
■■ Power button
■■ Power light
■■ Reset button
■■ Drive activity lights
■■ Audio jacks
■■ USB ports

10. Characteristics of Processors
• Hyper threading : This term refers to Intel’s Hyper-Threading Technology
(HTT). HTT is a form of simultaneous multithreading (SMT).
• Multicore: A processor that exhibits a multicore architecture has multiple
completely separate processor dies in the same package. The operating system
and applications see multiple processors in the same way that they see
multiple processors in separate sockets.
• Throttling : CPU throttling allows reducing the operating frequency of the CPU
during times of less demand or during battery operation.
• Speed : The speed of the processor is generally described in clock frequency
(MHz or GHz).

11. Important Memory Terms
• Parity checking
• Error-correcting code (ECC)
• Single- and double-sided memory
• Single-, dual-, and triple-channel memory

12. Type of Memory
 Dynamic random-access memory(DRAM)
Asynchronous DRAM
 FPM DRAM
 EDO DRAM
 BEDO DRAM
 Synchronous DRAM
 SDR SDRAM
 DDR SDRAM
 DDR2 SDRA
 DDR3 SDRAM
 DRDRAM
 SRAM
 ROM