Motherboard: Definition, Parts and Manufacturers

• A motherboard is an electronic platform connecting all computer parts.
• Motherboards house and connect all computer components.
• They enable communication between devices and the motherboard.
• Motherboards determine a system's capabilities and limitations.
• Motherboards are mounted inside the case with screws.
• Ports allow connection of internal components like video and sound cards.
• Motherboards have a socket for the CPU and slots for memory.
• They have ports for external connections like monitors, printers, etc.
• USB ports connect compatible devices.
• Common MB manufacturers include Intel, ASUS, Aopen, ABIT, Biostar, Gigabyte, and MSI.

Main Parts of Motherboard

• Northbridge with heatsink.
• Southbridge
• IDE Connector (x2).
• AGP Slot
• DRAM Memory Slot (x2)
• PCI Slot (x5)
• 20-pin ATX Power Connector
• CMOS Backup Battery
• CPU Fan & Heatsink Mounting Points.
• Connectors for Integrated Peripherals

CPU Socket

• Motherboards provide a single socket for the CPU.

Heatsink

• Special thermal conductor on the CPU (or other components).
• It reduces generated heat, cooling components like the GPU and Northbridge.

Fan

• Fans cool down the heatsink.
• Some gaming computers use liquid coolant heatsinks.

Clock Generator

• Circuit produces a clock signal for synchronizing operations.
• CPU clock speed is the frequency at which a processor executes instructions.
• Clock frequency is measured in MHz or GHz.
• The computer's operating speed is linked to the system clock speed
• PCs nowadays have clock speeds exceeding 1 GHz.

RAM Slots

• Slots facilitate the addition of RAM

Accelerated Graphics Port (AGP)

• This is used for graphic cards, mainly used by older motherboards.
• These are largely replaced by PCI-E x16

Chip Set

• Integrated circuit, provides support to CPU and I/O devices.

Northbridge

• Primary controller, coordinates data traffic to and from the CPU.
• Core component directly connected to the CPU.
• Usually comes with a heatsink.

Functions of Northbridge

• Handles communication between CPU, RAM, PCI Express, and Southbridge.
• Acts as a controller for bus speed.
• Connects the Southbridge to the CPU.
• In some newer Intel processors, the CPU performs the functions of the Northbridge.

Southbridge

• An IC chip, smaller than the Northbridge.
• Handles I/O functionality on the motherboard.
• CPU sends instructions to the Southbridge via Northbridge.
• Southbridge handles slower devices like ISA, PCI, IDE buses, audio, serial devices, USB ports, and SATA connectors.

PCI Slots

• PCI stands for Peripheral Component Interconnected.
• Hardware components attach to the motherboard.
• These slots connect various hardware components.
• PCI slots use a parallel bus.

PCI Express Slots (PCI-E)

• PCI-E represents Peripheral Component Interconnected express.
• PCIe is a newer, faster version of PCI = PCI-e uses a serial bus.

Complementary Metal Oxide Semiconductor (CMOS) backup battery socket

• Stores system data like the clock, date, hardware settings, BIOS config, boot sequences, and passwords.

CMOS Battery

• CMOS battery is a lithium-ion battery the size of a coin.
• When the CMOS battery dies, BIOS settings reset to default.
• The CMOS battery works even when the system is off, holding a charge for up to 10 years before needing replacement.

BIOS Chip

• Chip where the BIOS firmware is stored
• It is the first program that runs when the computer starts.
• Newer motherboards label it under UEFI BIOS, M_BIOS, or similar

Ports and Interfaces on Motherboard

• Motherboards have I/O sockets connected to ports and interfaces.
• Motherboard ports and interface allow external devices to connect.

PATA Port (Parallel Advanced Technology Attachment)

• Parallel port that is an IDE standard for connecting storage devices.
• Sends multiple bits of data at the same time.
• Cables have multiple data lines for parallel data transfer.

IDE (Integrated Drive Electronics)

• Electronic interface standard for connecting storage devices to the bus.

SATA Port (Serial Advanced Technology Attachment)

• 7-pin cable, shorter and more powerful than the PATA connector.
• Transfers one bit of data at a time.
• Used for connecting storage devices.

Serial Port

• Serial communication interface for sequential information transfer (one bit at a time).
• Used to connect old peripherals.
• Higher speed and greater standards, most commonly USB

Parallel Port

• connects old printers or parallel communication devices.

Digital Visual Interface

• Video display interface, connects a video source to display, from 1999

Display Port (DP)

• Digital display interface, connects a video source to display, from 2008
• Transports audio, USB, and other data.

PS/2 Port

• Named after IBM Personal System/2
• Used for connecting mice and keyboards.

Video Graphics Array port (VGA)

• Standard connector for computer video output.
• Devices still use VGA connectors, many replaced with DVI, HDMI, and DP.

Universal Serial Bus (USB)

• Industry standard for cables, connection, communication, and power between computers and peripherals.
• Includes 14 connector types; USB-C is the most recent and non-deprecated.

1394a Port

• Connects FireWire devices like video cameras.

RJ-45 Port

• Connects computers to a network hub or router via RJ-45 cable.

Audio Port

• To connect audio devices
• A is for audio centre/subwoofer
• B is for rear speaker out
• C is for side speaker out
• D is for audio line-in
• E is for audio line-out
• F is for microphone line-in

Power supply

• Supplies power to the motherboard, attached components and peripherals

Bus

• Physical connections between cables and printed circuits.
• Shared by components for communication.
• Three types of system buses exist: Data Bus, Address Bus, and Control Bus.

Data Bus

• Transfers data between computer components
• Affects data transfer speed based on lines.
• A 64-line data bus can transfer 64 bits at once.
• Data bus lines are bi-directional (CPU can read/write data to/from memory).

Address Bus

• Many components connect through buses.
• Each component has a unique ID (address).
• Components communicate using the address bus.
• The address bus is unidirectional, carrying info only one direction.
• Carries address of memory location from microprocessor to the main.

Control Bus

• Transmits commands/signals between components
• Manages info flow, indicating operation type and timing.

A Control Signal Includes:

• Timing information: Specifies time a device can use data and address bus.
• Command Signal: Specifies operation to be performed.