Essentials of Computer

ESSENTIALS OF COMPUTER

What Is Inside The CPU Box? Inside the CPU box are the motherboard, CPU, memory, internal storage and

power supply. Power SupplyCPU (Central Processing

Unit)

Power Supply

RAM (Random Access Memory

Hard DiskMotherboar

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CPU Box

The motherboard

Also called the system board is the main base of the computer hardware system. All parts, components and devices connect to the motherboard. The motherboard is also the host of the CPU, the memory and the other essential elements of the computer. All other components are usually connected by data cable.

CPU (Central Processing Unit)

The brain of the computer, is inside the CPU box placed on a special slot on the motherboard. The CPU is contained inside a small chip called microprocessor. The CPU processes all the basic and complex instructions given to it.

Memory

Is where data and programs are placed for execution by the CPU. The memory is also directly connected to the motherboard through a slot also called socket. There are three kinds of memories.

a. RAM (Random Access Memory) also called the main memory. Data and programs are placed here when the CPU is processing. Information in the RAM are lost when power is turned off.

b. ROM (Read Only Memory) stores important programs for example, to start the computer. ROM information cannot be changed even when power is off.

c. CMOS (Complimentary Metal-Oxide Semiconductor) stores the data, calendar and current time of the computer. It is powered by batteries so that even when the computer is off information inside it, remains.

Internal Storage

is where data is kept for future use. This storage retains information even when power is turned off. The common internal storage is the hard disk but solid-state drives, hard disk without moving parts, is now popular.

Power Supply

The CPU, motherboard, hard disk and other components inside the CPU box get their power source from the power supply.

The Central Processing Unit (CPU) The CPU executes a step by step instructions in its

memory called the program. The CPU has two basic components; the arithmetic logic (ALU) and the control unit. These two components work together to do the computer processing.

The arithmetic logic unit (ALU) does arithmetic and logical operations of the computer. The arithmetic function includes the basic math calculations such as addition, subtraction, multiplication and division. The logical function on the other hand compares whether a data is greater, less or equal to another and then certain actions occurs.

The control unit functions just like a traffic cop that directs what operation the CPU does first, next and so on. It determines what numbers to add and what data to compare in the arithmetic logic unit.

Machine Cycle There are four basic steps that the CPU does to process its

operation: fetch, decode, execute and store. The process is repeated again until the last instruction. This is also called the machine cycle.

FETCH – is the process of getting a program instruction or data from memory.

DECODE – is the process of translating these instructions or data that the CPU can understand and execute upon.

EXECUTE – is the process of carrying out the command. It is either an arithmetic or logical operation.

STORE – is the process of writing the result to memory. This memory is in the CPU itself and they are called registers. This memory is not the RAM or the hard disk.

REGISTERS

- Inside the CPU are small but high-speed data storage called registers. Registers hold data and instructions temporarily but are transferred to the CPU for processing at very high speeds. Processors have different types of registers some are used to store location of instructions, store instructions while the CPU is decoding them, store data while ALU computes and stores results of ALU calculation or comparison.

SYSTEM CLOCK- The CPU system clock is generated by a

quartz crystal. The system clock provides the fixed sequence in time that cannot be varied. The number ticks in one cycle is called clock rate. The faster the clock rate, the faster is processor clock rates are measured in gigahertz (GHz). Giga is a prefix denoting billion and hertz is one cycle per second. Therefore, one gigahertz (GHz) is one billion ticks of the system clock per second. CPU that is rated at 1.6 GHz has 1.6 billions processor clock cycles per second. Therefore, it is preferable to have a processor with high clock rate.

CPU COOLING

The CPU chip generates a lot of heat when processing and may burn up if not cooled. A cooling system is needed to ensure that the processor chip is cooled to a level that it operates efficiently. Most processors are provided with cooling fans but these may not be enough, additional external cooling is needed.

HEAT SINK

Is a metal component attached to the CPU with fins designed to dissipate heat therefore cool the processor. Heat is absorbed by the heat sink and is dispersed to the air by the fin. Sometimes heat pipes are used to blow heat away.

Other computers use water cooling just like cars. Water flows from the processors to the radiator-type grill that cools the water then water returns to the CPU to cool it again.