Internal Components of CPU

CPU CPU

A CPU (Central Processing Unit), or processor as it is sometimes called, is

the main chip in the computer and is located on the Motherboard.

The CPU processes the computer’s data and exchanges it with the other

components and peripherals.

CPU’s come in different speeds, the most of common of which are between

500MHz - 800MHz. The speeds are measured in Mega Hertz (MHz) and

even Giga Hertz (GHz). Most modern computers have two processors (Intel

Dual Core Processor).

The CPU is often referred to as the brain of the computer.

Motherboard

The Motherboard, or logic board as it is known in Macintosh computers, is

the main circuit board in the computer. The Motherboard contains many

components like the RAM, CPU, expansion slots and the heat sink. The

motherboard connects all these peripherals together.

1. BACK PANEL AND CONNECTORS

Back panel is the portion of motherboard that allows you to connect

external devices such as your monitor , speakers , keyboard and mouse.

Back panel is on the edge of motherboard.

Connectors and ports for connecting the computer to external devices such

as display ports, audio ports, USB ports, Ethernet ports, PS/2 ports etc.

Computer

Power Cord dvi-cable

Ethernet Cable

Audio Jack

hdmi Cable

Ps2- cable

vga-cable

USB

cable

2.PCI

PCI: Peripheral Component Interconnect

PCI is a computer bus used for attaching peripheral devices to a computer motherboard.

PCI provides a shared data path between CPU and peripheral controllers in every computer models from laptops to mainframes.

Slot for older expansion cards such as sound cards, network cards, connector cards . It supports both 32-bit and 64-bit data paths.

Have been largely replaced by PCI-Express x1 slots

3. PCI Express x1 Slots

Slot for modern expansion cards such as sound cards, network cards (Wi-Fi,

Ethernet, Bluetooth), connector cards (USB, FireWire, eSATA) and certain

low-end graphics cards.

4. PCI Express x16 Slot

Slot for discrete graphic cards and high bandwidth devices such as top-end

solid state drives.

5.NORTHBRIDGE

Also known as Memory Controller Hub (MCH).

Chipset that allows the CPU to communicate with the RAM and graphics card.

It is a microchip on some PC motherboards and is connected directly to the CPU and thus responsible for tasks that require the highest performance.

It is usually paired with southbridge,also known as I/O controller hub.

In systems where they are included,these two chips manage communications between CPU and other parts of motherboard and constitute core logic chipset of PC motherboard.

6.CPU Socket

Processor

A processor is the logic circuitry that responds to and processes the basic

instructions that drive a computer.

The term processor has generally replaced the term CPU.The processor in a

personal computer or embedded in small devices is often called a

microprocessor.

Two typical components of CPU are:

1. Arithmetic Logic Unit(ALU)

2. Control Unit(CU).

7. ATX 12V Power Connector

Connects to the 4-pin power cable of a power supply unit which supplies

power to the CPU

8. Front Panel USB 2.0 Connectors

Connects to USB 2.0 ports at the front or top of a computer case.

9.Front Panel Connector

Connects to the power switch, reset switch, power LED, hard drive LED

and front audio ports of a computer case.

10. IDE Connector

Connects to older hard drive disks and optical drives for data transfer.

Have been replaced over by SATA connectors.

11. CMOS Battery

Supplies power to store BIOS settings and keep the real-time clock running.

The CMOS battery found on most motherboards is the CR2032 lithium coin

cell.

12.South Bridge

Also known as the Input/Output Controller Hub (ICH).

Chipset that allows the CPU to communicate with PCI slots, PCI-Express x

1 slots (expansion cards), SATA connectors (hard drives, optical drives),

USB ports (USB devices), Ethernet ports and on-board audio.

13. SATA Connectors

Connects to modern hard disk drives, solid state drives and optical drives

for data transfer.

14. Fan Headers

Supplies power to the CPU heat sink fan and computer case fans.

15. RAM Slots

Random access memory (RAM) is fast-access main memory that attaches

directly to the motherboard, and is used to store programs that are currently

running.

RAM is a type of volatile memory which means it requires electricity to

store data, so when the computer is powered down all the memory is wiped.

RAM is a set of integrated circuits that allow the stored data to be accessed

in any order (why it is called random).

There are many types of RAM including SRAM (Static Random Accessing

Memory), DRAM (Dynamic Random Accessing Memory) and SO-DIMM

RAM. All these do similar jobs to the RAM.

16. ATX Power Connector

Connects to the 24-pin ATX power cable of a power supply unit which

supplies power to the motherboard.

17. mSATA Connector

Connects to a mSATA solid state drive. In most cases, this SSD is used as

cache to speed up hard disk drives, but it's possible to re-purpose it as a

regular hard drive.

18. Front Panel USB 3.0 Connector

Connects to USB 3.0 ports at the front or top of the computer case.

19. Power & Reset Button

Onboard button to turn on, turn off and reboot the computer.

This motherboard component is more common among high end boards

.

ROM

Read Only Memory is a class of storage medium which is used in

computers and many other electronic devices.

It is a non-volatile memory i.e. its contents are not lost when the power is

switched off.

Data stored in ROM can only be modified slowly, with difficulty, or not at

all, so it is mainly used to distribute firmware.

Available in 2 types:

a. Erasable Programmable ROM(EPROM)

b. Electrically Erasable Programmable ROM(EEPROM)

POWER SUPPLY

The Power Supply Unit supplies all the computer components the required

power (electricity). The Power Supply Unit changes AC (Alternating Current)

from the mains supply into DC ( Direct Current) which is used by the

components.