What Is SYSTEM UNIT???? Zassssssssssss......

•       The system unit is a case that contains electronic  components of the computer used to process data.
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•         The case of the system unit, sometimes called the chassis is made of metal or plastic and protects the internal electronic components from damage.
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•         All computers and mobile devices have a system unit. 

System unit also known as :

• "computer chassis",
• "tower", 
• "base unit" or simply "case".
• "system unit", 

Also sometimes incorrectly referred to as the "CPU"

• Main components inside the computer:

1) Motherboard
2) Adapter cards
3) Processor 
4) Memory

MOTHERBOARD

•The motherboard is the main circuit board of the system unit

- A computer chip contains integrated circuits.

The functions of the motherboard are:

lHolds many components of the system.

lProvides connectors for other peripherals.

Basic Component of motherboard :

lProcessor Slot

lMemory Slots

lAdapter Card Slots

PROCESSOR SLOT

- Slot on the motherboard that houses a CPU and forms the

electrical interface with the CPU.

MEMORY SLOT

lSlots on the motherboard that hold memory modules.

lTo connect RAM and get faster of the performance of computer.

ADAPTER CARD SLOTS

lSlots on the motherboard that can hold adapter cards.

lFor adding more memory, graphics capabilities and support for

special devices.

CPU ( Central Processing Unit )

•The processor, also called the central processing unit (CPU),

interprets and carries out the basic instructions that operate a

computer.

•CPU speeds is measured in gigahertz (GHz). 

•CPU Components :

–Control unit 

–Arithmetic logic unit (ALU)

 CONTROL UNIT

lIs the component of the processor that directs and coordinates most of the operations in the computer.

lThe control unit has a role much like a traffic cop; it interprets each instruction issued by a program and then initiates the appropriate action to carry out the instruction.

ARITHMETIC LOGIC UNIT

lPerforms arithmetic, comparison and other operations.

lArithmetic operations include basic calculations such as addition, subtraction, multiplication and division.

lComparison (logical) operations involve comparing one data item with another to determine whether the first item is greater than, equal to or less than the other item.

MACHINE CYCLE

lThe operations performed by the CPU to execute any instruction.

lFor each instruction, a processor repeats a set of 4 basic operations, which compromise a machine cycle.

ADAPTER CARD

• An expansion slot is a socket on the motherboard that can hold

an adapter card

• An adapter card enhances functions of a component of the

system unit and/or provides connections to peripherals

• A peripheral is a device that connects to the system unit and is

controlled by the processor in the computer. Examples: modems,

printers, scanners, keyboards, sound card and video card