1. CENTRAL PROCESSING UNIT CPU (microprocessor)
The central processing unit (CPU) performs operations on data. Fetches instructions from main memory. stores data, intermediates results and program. It controls the operation of all parts of computer
Carries out the operations commanded by the instructions(program)
Each instruction produces some outcome
A program is an entire sequence of instructions
Instructions are stored as binary numbers
Binary number - a sequence of 1’s and 0’s

2. Identify the CPU on the motherboard

3. Identify the CPU on the motherboard

4. EXAMPLES OF MICROPROCESSOR
PENTIUM 4
PENTIUM R
PENTIUM 3
MAC
PENTIUM 2
Cyrix
CELRON
DUAL CORE

5. CPU COMPONENTS
In most architectures it has three parts: an arithmetic logic unit (ALU), a control unit and a set of registers, fast storage locations.

6. CPU COMPONENTS: ALU Control Unit A set of registers

7. Central Processing Unit
Output
Devices
Cache
Memory
Primary
Storage
Secondary
Control
Unit
ALU
Special
Purpose
Processors
Input

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ALU
The actual processing of the data and instruction are performed by Arithmetic logic Unit
It Accepts and process data
The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparison.
Data is transferred to ALU from storage unit when required
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9. ALU Arithmetic operations: Logical operations:NOT ;AND;OR; XOR
Increment
Decrement
Add
Subtract
Multiply
Divide
Logical operations:NOT ;AND;OR; XOR
Comparing
Selecting
Merging
Matching of data

10. Control Unit
Like the part of the human brain that control the operation of each part of the body.
Controlling is achieved through wires (form Control unit to ALU) that can be on/off.
4 wires  16 operations

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Control Unit (CU)
The Control Unit acts like the supervisor i.e
controls
It extracts instructions from memory and decodes and executes them, and sends the necessary signals to the ALU to perform the operation needed.
The control unit determines the sequence in which computer programs and instructions are executed.
Process programs stored in the main memory. interpret the instructions and issue signals for other units of the computer to execute them.
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12. Register
A special, high-speed ,stand-alone ,temporary storage area within the CPU. All data must be represented in a register before it can be processed.
For example, if two numbers are to be multiplied, both numbers must be in registers, and the result is also placed in a register.
The power and speed of a CPU determined by
the number of registers that a CPU has and
the size of each (number of bits)
For example a 32-bit CPU is one in which each register is 32 bits wide. Therefore, each CPU instruction can manipulate 32 bits of data.

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Registers:
The CPU processes data and instructions with high speed, there is also movement of data between various units of computer.
It is necessary to transfer the processed data with high speed and remember the various addresses of data for effective functioning of CPU.
So the computer uses a number of special memory(working space/temporary storage) units called registers.
They are not part of the main memory but they store data or information temporarily and pass it on as directed by the control unit.
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14. Register Organization • Total of bit registers — 31 are referred to as general purpose register although some such R15 (PC) have special purposes — Six program status registers • Registers are arranged in partially overlapping
Program status registers
Current Program Status Register
General Purpose Registers
Program Status Register
User Visible Registers
Control and Status Registers

15. Registers Types of PC (Program Counter) Current Instruction Register
Keep track of the instruction currently being executed.
Incremented after execution of the instruction.
Current Instruction Register
Store the instruction currently being executed
Data Registers
Hold data before it can be processed

16. Functions of CPU Register
Temporarily store data required for processing
Stores addresses of data being executed
Determines the power and speed of CPU- i.e its determinant is the number and size of cpu registers
Pass data onto other parts of computer as directed by the control unit.
it helps transfer data and instructions with high speed
Hold data before it can be processed
Store the instruction currently being executed
Keep track of the instruction currently being executed
Incremente after execution of the instruction

17. Measurements of Computer Power
Clock speed: electronic pulses used to synchronize processing. Faster clock speeds result in more operations in a give amount of time. Measured in megahertz (MHz).
Bus width: determines how much data can be transferred at any one time. 16 bit, 32 bit, 64 bit.
IBM’s Microchannel (MCA) Architecture vs EISA (open architecture)
Word size: number of bits/bytes manipulated at once. Same as the bus width.
Other determinants include main memory capacity, MIPs.
This is not the same as throughput but it can affect throughput.. 18