Central Processing Unit (CPU)

A Central Processing Unit is also called a processor, central processor, or microprocessor. It carries out all the important functions of a computer. It receives instructions from both the hardware and active software and produces output accordingly. It then performs calculations, manipulates data, and produces output based on those instructions. It stores all important programs like operating systems that manage the computer’s resources and allows you to interact with it and application software that you use to perform tasks like word processing, web browsing, and gaming. Your computer couldn’t execute these essential programs without the CPU.

CPU also helps Input and output devices to communicate with each other. The CPU translates these inputs when you click, move the mouse, or click on a key on the keyboard, and it works with the relevant software program to produce the intended result. The CPU ensures that the input and output devices communicate without any troubles, whether it means printing a paper, playing music through the audio system, or showing text on the display screen. Owing to these features of CPU, it is often referred to as the brain of the computer.

CPU is installed or inserted into a CPU socket located on the motherboard. Furthermore, it is provided with a heat sink to absorb and dissipate heat to keep the CPU cool and functioning smoothly.

Central Processing Unit’s – History and Evolution

Computers have become a part of our everyday lives, but the first computer was developed in 1946 at the University of Pennsylvania!

• Electronic Numerical Integrator and Computer or ENIAC was the processo
• Alan Turing and John von Neumann presented the reprogramming feature that is so widely utilised nowadays. A modern computer’s architecture is based on von Neumann’s design.
• Microprocessors have come a long way since Intel’s 4004 – the first microprocessor ever developed.
• We’ll take a look at what’s happened so far.
• In the early 1970s, Ted Hoff and others at Intel came up with the idea for the first Processor, which was then produced by the company.
• Intel’s 4004 processor was the company’s first processor.

1971 – Intel 4004

• Designed by Intel’s Federico Faggin and Ted Hoff and Busicom’s Masatoshi Shima, it went on sale on November 15, 1971. “
• 2300 transistors with pMOS technology were used in the device.
• There were a total of 46 instructions.
• The intended clock speed was 1 MHz, but it was only achieved at 740 kHz.
• As the world’s first microprocessor, it powered the Busicom 141-PF calculator, which is still in use today.

1972 – Intel 8008

• Introduced in August 1972, it is also known as MCS-8.
• CTC’s Victor Poor and Harry Pyle worked on it, as did Intel’s Ted Hoff, Faggin, Stanley Mazor, and Hal Feeney.
• There were 3500 transistors in it.
• But it was slower than the 4004.
• This computer had a clock speed of 0.5 MHz and a total number of 48 instructions.
• Micral and SCELBI were the first personal computers to use it.

1974 – Intel 8080

• Intel 8080 was introduced in 1974.
• Faggin, Mazor, and Masatoshi Shima created it in April 1974.
• The clock speed was increased to 2 MHz, and it used 6000 transistors and nMOS technology. »
• Most notable was the separation of the address (16 bit) and data (8 bit) buses, which was a major advancement.
• It also had 256 input/output ports.
• The MITS Altair 8800 and IMSAI 8080 both used it.
• Similarly, the main processor in Space Invaders (an arcade video game) was the 8080 microprocessor.

1974 – Motorola 6800

• The Motorola processor had no I/O ports.
• I/Os were memory-mapped.
• In addition, the instruction set contained 72 instructions at a clock speed of just 2 MHz
• HCF (Halt and Catch Fire) opcode was used for the first time, preventing the processor from responding to any interrupts until it was reset.
• Motorola introduced HCF, a self-testing feature, for the first time.

1977 – Intel 8085

The processor was also used as a microcontroller, operating on a +5V supply, unlike the other processors formed so far.

• Von Neumann architecture was used for the first time.
• “It was constructed with nMOS technology and 6500 transistors.”
• There were 256 instructions in the instruction set.
• In NASA and ESA space explorations, the radiation-hardened version was employed.

1978 – Intel 8086

• The clock speed was designed to be 10MHz.
• Bruce Ravenel was part of the architecture development team, which included Stephen P. Morse.
• Jim McKevitt, John Bayliss, and William Pohlman designed Logic, with William Pohlman serving as the project manager.
• Mycron 2000 was the first microcomputer to use it.

1979 – Intel 8088

• HMOS-based 8088 was launched on July 1st.
• PLCC (plastic leaded chip carrier) package was available as well as a 40-pin DIP package. »
• There was only 8-bits of data in the path, however.
• 10 MHz was the intended frequency.
• 8088 was the basis for the original IBM PC.

1987 – SPARC

• It’s a Sun Microsystems processor.
• It had a 40 MHz clock speed.
• 8 million transistors and 256 I/O pins were used to build it.
• According to the TOP500 list, Fujitsu’s K Computer is ranked number one among the world’s 500 fastest supercomputers.
• It was based on the SPARC architecture.

1991 – Am386

• There was a striking similarity between this AMD (Advanced Micro Devices) processor and Intel x86 processors.
• In terms of clock speed, the processor was a competitor to Intel’s.
• Many manufacturers chose AMD’s floating-point unit because of its excellent performance.

1993 – Pentium Processor

• P5 was the first Pentium processor.
• Two models were available: 510-pin version and 567-pin
• 1 million transistors were used in its construction.
• At the time, this 32-bit processor was the most advanced processor available.
• There were two instructions that could be executed at the same time in this superscalar x86 microarchitecture, speeding up computation.

1995 – Pentium Pro

• Pentium II was the first Pentium processor.
• It was packaged in a ceramic multi-chip module (MCM) with 387 pins, which was a first for the industry.
• In addition to its dual processor configuration, it has a 200 MHz clock speed.
• In order to build this processor, approximately 5.5 million transistors were used.
• MMX instructions were not included.
• This processor was utilised in ASCI Red, which had teraFLOP (one trillion floating-point operations per second) performance or results.

1997- Pentium II

• The Pentium II processor family was introduced on May 7 and offered a wide range of processors.
• With each new model, the clock speed was steadily increased to 450 MHz.
• A slot or socket module was used instead of the traditional processor.
• Because of this, computer manufacturers were able to fit it into a small space.
• Under this umbrella, a number of processors were introduced: Some of these were Klamath;
• Deschutes; Pentium II overdrive; Tonga, etc.
• It had a heatsink/fan combination that could be removed, which helped with heat dissipation.

1999-Pentium III

• It was introduced on February 26th.
• The SSE instruction was added to the previous model to speed up floating-point calculations.
• Like Pentium II, this processor was released in two versions: Celeron (low-end version) and Xeon (high-end version) (High-end version).
• The following processors are included in this family: Katmai; Coppermine; Coppermine T and Tualatin.
• PSN (Processor Serial Number) was introduced in the production process that formed the processor’s unique identity.

1999 – Athlon

• Athlon was announced by AMD on June 23.
• A clock speed of 800 MHz was achieved by using 37 million transistors.
• It came in a 453-pin PGA (Pin Grid Array) package.
• It was faster than Intel’s Pentium III, which made Athlon a legitimate competitor. »
• That made it the first processor to reach the 1 gigahertz speed mark in history.
• Enhanced 3DNow! was first launched, which sped up by 2-4 times.

2000-Pentium IV

• Pentium IV was Intel’s new single-core processor, with clock speeds ranging from 1.3 GHz to 3.08 GHz.
• When it came to packaging, the 423-pin processor was available in both OLGA and PPGA (Plastic Pin Grid Array) formats.
• The processors that fall under this category include; Willamette; Northwood; Pentium 4-M; Mobile Pentium etc
• Processors in this family were the first to use the NetBurst architecture.

2003-Pentium -M

• This was an Intel single-core mobile processor.
• It was designed with a clock speed is 2.26 GHz.
• There are two processors in this family: Banias; Dothan.
• TDP of 24.5 watts and clock speed of 1.7GHz for Banias
• DOTHAN: Die of 90 nanometers and 2.16 gigahertz, with 21-watt TDP.
• It was used for the first time in the Intel Carmel notebook, Centrino-brand.

2006-Core 2

• E6320 is another name for Intel Core 2 brand, which was launched on July 27, 2006. It had clock speed of upto 3.5 GHz .
• Single-core, dual-core, and quad-core processors were introduced under this family.
• The processor is no longer available for purchase.
• The desktop processors under this brand include:
• The Conroe XE; Allendale; Wolfdale
• We have Allendale XE, Wolfdale XE, and more.
• This brand’s laptop processors include:
• Merom XE; Penryn; Merom
• As well as Merom-L and Penryn XE
• Using a slower clock speed, the processor was able to conserve battery power.

Latest Technology- CPU

Since the launch of the 4004 microprocessor, the technology has advanced significantly.

A smaller chip, faster clocks, and larger caches have all resulted in a smaller chip and faster clocks.

Products based on Intel’s microarchitecture were introduced in 2011.

It has been able to produce dies with a 32-nanometer thickness.

Included is Intel Quick sync, which is a hardware-based video encoding and decoding solution from Intel.

Interconnecting the different parts of the processor is also made easier with an improved 256-bit/cycle ring bus connect.

• This processor has a transistor count of 2,27 billion.
• The designed clock speed is 3.6 GHz.
• Cougar Point Chipset motherboards in the 67-series were recalled by Intel due to a hardware issue.
• The following series are part of this family:Intel Pentium: Celeron: Core i3: Core i5: Core i7: Core i7 Extreme: It has the vPro feature that has the ability to delete data from a hard drive via 3G signals or Ethernet or Internet.

Ivy Bridge

• It was announced in 2011 that Intel would be releasing a 22-nanometer die processor called Ivy Bridge, but it was only released on April 29, 2012.
• The use of 3D (tri-gate) transistors allows for a smaller die.
• In comparison to 2D transistors, 3D transistors reduce power consumption by nearly 50%.
• PCI Express is also supported, as is DirectX 11, which improves the graphics.
• 80 GHz is the clock speed of the processor.
• According to reports, they have a temperature 20oC higher than Sandy Bridge.
• Under this family, there are the following desktop models:
• i3, i5, and i7 Processors
• Mobile that fall under this category include: i3, i5, and i7 Core Processors
• It is one of the tick version of sandy bridge.

Latest – Fifth Generation CPU or Central Processing Units

• The fifth generation Central Processing Unit is based on Artificial Intelligence.
• A still-under-development Central Processing Unit.
• The use of voice recognition is an example of a current application.
• By the way, it’s still being worked on right now.
• AI aims to create an intelligent device that can respond to natural language input and can learn on its own.

Components of CPU

Generally, a CPU has three components:

• ALU (Arithmetic Logic Unit)
• Control Unit
• Memory or Storage Unit

Control Unit:

The Control Unit (CU) is a vital part of the Central Processing Unit (CPU) and is accountable for the overall performance of a computer system. It is the circuitry in the control unit, which makes use of electrical signals to instruct the computer system for executing already stored instructions. It takes instructions from memory and then decodes and executes these instructions. So, it controls and coordinates the functioning of all parts of the computer.

The Control Unit’s main task is to maintain and regulate the flow of information across the processor. It serves as a traffic controller, ensuring that information and instructions are efficiently transferred among the various elements of the computer system. It manages the order in which instructions are executed and synchronizes the activities of various units within the CPU. It does not take part in processing and storing data. Instead, it serves as an overseer, coordinating the actions of other CPU parts to guarantee that instructions are carried out accurately and in the right order.

The Control Unit achieves coordination within the CPU through a series of steps:

• Fetch: The Control Unit retrieves an instruction from the computer’s memory. It accomplishes this by accessing the memory location provided by the program counter (PC), which contains the address of the next instruction to be executed.
• Decode: Once the instruction is fetched, the Control Unit decodes it. It breaks down the instruction into its constituent elements, which include the operation code (opcode) and any associated operands. The operands supply the data or memory locations on which the operation will be completed, while the opcode suggests the kind of operation to be done.
• Execute: After the instruction is decoded, the Control Unit initiates the execution phase. It coordinates the necessary actions within the CPU’s functional units, such as the arithmetic logic unit (ALU), to perform the specific operation indicated by the instruction. This may involve calculations, data manipulations, or control operations.
• Store: Once the instruction is executed, the Control Unit updates the necessary registers and flags to reflect the operation results. This could involve storing the result in a register, updating the program counter to indicate the address of the next instruction, or modifying status flags that provide information about the outcome of the operation (e.g., zero flags, carry flags).
• Repeat: After updating the necessary components, the Control Unit repeats the process by fetching the next instruction from memory. It increments the program counter to point to the next instruction’s address, and the cycle continues.

This fetch-decode-execute cycle is repeated for each instruction in the program, allowing the Control Unit to coordinate the sequential execution of instructions and ensure that the computer system performs the required tasks.

The Control Unit ensures the correct information flow and guides the CPU’s actions during this process. It eventually aids in the general operation of the computer system by allowing the CPU to carry out the required operations and computations through the fetching, decoding, and execution of instructions.

ALU:

It is the arithmetic logic unit, which carries out arithmetic and logical operations. Included in the list of arithmetic operations are addition, subtraction, multiplication, division, and comparisons. Data selection, comparison, and merging are the primary logical operations. More than one ALU may be present in a CPU. ALUs can also be used to keep track of timers that assist in running the computer.

The ALU consists of two main subsections: the Arithmetic Section and the Logic Section.

• The ALU’s Arithmetic Section conducts mathematical operations. It performs fundamental mathematical operations including addition, subtraction, multiplication, and division. For mathematical computations in several applications and programmes, these processes are necessary. Other operations, such as bitwise operations and incrementing or decreasing values, can also be handled by the Arithmetic Section.
• The ALU’s Logic Section is in charge of performing logical operations. Data manipulation based on logical conditions is referred to as logical operations. These operations include choosing or removing certain data elements or fields, comparing values to identify connections (such as equal, greater than, or less than), and merging or combining data in accordance with logical principles. Decision-making, data filtering, and data processing tasks frequently employ logical operations.

The ALU’s arithmetic and logical functions are crucial for the execution of instructions within the CPU. The ALU is responsible for carrying out the necessary arithmetic or logical operation specified by the instruction when retrieved and decoded by the Control Unit. For instance, the Arithmetic Section of the ALU will perform the addition operation and output the result if an instruction calls for adding two integers.

Sometimes, a CPU may contain multiple ALUs to enhance its processing capabilities. Multiple ALUs can work simultaneously, allowing for parallel execution of operations and speeding up computation tasks. This is especially beneficial in CPUs with multiple cores or processors designed for high-performance computing.

Memory or Storage Unit

A computer system’s memory or storage unit maintains instructions, data, and intermediate outcomes. It acts as a database that other computer components may access and save data in as needed. This device has numerous names because of its numerous functions, including internal storage unit, main memory, primary storage, or Random-access reminiscence (RAM).

The memory unit’s capability directly affects the computer’s speed, power, and normal performance. A memory unit with a larger ability allows for storing more data and instructions, resulting in an improved machine capacity to handle complicated tasks efficiently.

A computer system commonly has two types of memory: primary and secondary.

• Primary memory, often called RAM, is the main memory of a computer. It closely collaborates with the CPU to quickly store and retrieve data. RAM allows the computer to access information randomly, which means it can retrieve any piece of data without going through everything in order. RAM acts as a momentary workspace where the computer stores the information and applications it is now utilizing. RAM is a volatile memory, so anything saved inside is lost when the machine is switched off. How many programs can run simultaneously and how much data can be processed simultaneously depends on the RAM capacity.
  
• Secondary memory includes hard disk drives (HDDs), solid-state drives (SSDs), and external storage devices. Computer systems are designed to store data for extended periods, even if powered off. Secondary memory, unlike RAM, is non-volatile and maintains records even in the absence of power. It is the storage location for operating systems, software applications, documents, and user data. Secondary memory has a larger capability in comparison to RAM. While accessing data from secondary memory takes longer than primary memory, it gives the advantage of long-term data retention.
  

Some functions of the Memory unit

• Storage: The memory unit stores instructions, data, and intermediate results for the computer to perform tasks.
• Retrieval: The computer can access stored information quickly and efficiently, enabling the processor to retrieve data and instructions during program execution.
• Temporary Storage: The memory unit provides temporary storage (RAM) for actively running programs, allowing the CPU to access and manipulate data quickly.
• Data Transfer: It facilitates the transfer of data between the CPU and other components of the computer system, ensuring smooth communication and efficient processing.
• Fast Access: The memory unit offers fast access to data and instructions, reducing delays in program execution and enhancing overall system performance.
• Random Access: It enables the CPU to retrieve data from any location in the memory unit without searching sequentially, allowing for quick and random access to information.

What is CPU Clock Speed?

The clock speed of a processor, often known as the CPU clock rate, is an important component. The clock speed of a CPU or a processor refers to the number of instructions it can process in a second. It is measured in gigahertz. For example, a CPU with a clock speed of 4.0 GHz means it can process 4 billion instructions in a second.

The number of instructions a CPU can execute in a specific time is determined by the CPU’s clock speed. Each instruction represents a fundamental CPU activity, such as transferring data or doing mathematical calculations. The clock speed determines how quickly these instructions are executed. A higher clock speed allows the CPU to process more instructions per second, enhancing overall performance.

Consider an example with a factory production line to understand better how clock speed affects CPU performance. The clock speed represents the speed at which the conveyor belt moves, bringing workpieces to different stations. The faster the conveyor belt moves; the more workpieces can be processed in a given time.

Note: The entire performance of a CPU is not determined by the clock speed alone. The processor’s architecture and design are also quite important. The effectiveness of different CPU architectures in carrying out instructions can vary. Therefore, CPUs with lower clock rates but superior architecture may perform better than CPUs with greater clock speeds but inefficient designs.

Modern CPUs also frequently use techniques like multi-core architectures and instruction pipelining to boost speed. To increase processing power overall, multi-core CPUs include numerous independent processing units (cores) that may carry out instructions concurrently. The CPU may execute many instructions simultaneously using instruction pipelining, significantly enhancing efficiency.

Because of advances in semiconductor technology, CPU clock rates have been rising continuously over time. Early CPUs operated at clock speeds measured in megahertz (MHz), but with technological progress, GHz speeds became the norm. Some high-end CPUs even surpassed the 5 GHz mark.

Types of CPU:

CPUs are mostly manufactured by Intel and AMD, each of which manufactures its own types of CPUs. In modern times, there are lots of CPU types in the market. Some of the basic types of CPUs are described below:

• Single-Core CPUs
• Dual-Core CPUs
• Quad-Core CPUs
• Hexa-Core CPUs
• Octa-Core CPUs
• Multi-Core CPUs

Single Core CPU

Single Core is the oldest type of computer CPU, which was used in the 1970s. It has only one core to process different operations. It can start only one operation at a time; the CPU switches back and forth between different sets of data streams when more than one program runs. So, it is not suitable for multitasking as the performance will be reduced if more than one application runs. The performance of these CPUs is mainly dependent on the clock speed. It is still used in various devices, such as smartphones.

But as technology developed, multi-core CPUs proliferated and now provide better multitasking skills. These CPUs can execute several instructions simultaneously due to their numerous processing cores. Single-core CPUs are less popular in desktop and laptop computers, although they are still used in embedded systems and mobile phones. Smartphones often use single-core or dual-core CPUs that are particularly made for power efficiency to balance performance and battery life.

Dual Core CPU

As the name suggests, Dual Core CPU contains two cores in a single Integrated Circuit (IC). Although each core has its own controller and cache, they are linked together to work as a single unit and thus can perform faster than the single-core processors and can handle multitasking more efficiently than Single Core processors.

A dual-core CPU’s two cores enable the execution of many tasks in parallel. Each core can independently execute instructions, enabling parallel processing. This capability significantly improves multitasking performance compared to single-core processors. With dual-core CPUs, users can run multiple applications simultaneously without experiencing significant performance slowdowns.

Dual-core CPUs offer benefits beyond multitasking. They can also enhance performance for single-threaded applications. Since each core can handle instructions independently, tasks that cannot be parallelized can still benefit from the dual-core architecture. One core can focus on running the main application, while the other handles background processes or system tasks. This division of work ensures a smoother user experience and improves overall system responsiveness.

Quad Core CPU

This type of CPU comes with two dual-core processors in one integrated circuit (IC) or chip. So, a quad-core processor is a chip that contains four independent units called cores. These cores read and execute instructions of CPU. The cores can run multiple instructions simultaneously, thereby increases the overall speed for programs that are compatible with parallel processing.

Quad Core CPU uses a technology that allows four independent processing units (cores) to run in parallel on a single chip. Thus, by integrating multiple cores in a single CPU, higher performance can be generated without boosting the clock speed. However, the performance increases only when the computer’s software supports multiprocessing. The software which supports multiprocessing divides the processing load between multiple processors instead of using one processor at a time.

Thanks to Quad-core processors’ ability to divide the processing burden among several cores, multiple processors can operate simultaneously instead of one at a time. Certain software supports this multiprocessing capacity, which improves productivity and speeds up processing times, especially for jobs that can be broken down into smaller subtasks and carried out concurrently.

Quad-core CPUs, in particular, provide advantages in terms of increased efficiency and quicker processing for multitasking and computationally heavy jobs. With four cores, the CPU can divide the workload more equally, enabling quicker reaction times and more fluid multitasking. In jobs like video editing, 3D graphics, and gaming, where simultaneous execution of numerous tasks is essential, quad-core CPUs excel in parallel processing.

Hexa-Core CPUs

Hexa-core CPUs are computer processors that include six separate cores on a single integrated circuit (IC) or chip. Each core functions as a separate processing unit that can perform computations and commands. With six cores, processing power may be boosted, and performance can be enhanced.

Regarding multitasking and managing resource-intensive tasks, Hexa-core CPUs provide substantial benefits. The CPU can perform numerous tasks simultaneously with six cores by distributing the burden among them for more effective processing. Users may operate many programs simultaneously without noticeably encountering performance slowdowns or delays, such as web browsers, video editing programs, and gaming programs.

Hexa-core CPUs also excel in applications that demand significant computational power, such as video editing, 3D rendering, scientific simulations, and virtualization. These tasks can be distributed across multiple cores, resulting in faster processing and reduced waiting times.

Octa-Core CPUs

Octa-core CPUs are computer processors with eight separate cores on a single integrated circuit (IC) or chip. Each core performs as a separate processing unit that can perform calculations and commands. An octa-core CPU’s eight cores considerably boost processing power and overall performance.

Octa-core CPUs excel at performing demanding workloads and have impressive multitasking capabilities. With eight cores, the CPU can effectively manage multiple simultaneous tasks. The workload is distributed across the cores, allowing for efficient processing and faster completion of tasks. This means users can run numerous applications simultaneously without experiencing significant performance slowdowns or system lag.

The key advantage of octa-core CPUs is their ability to execute instructions in parallel. Each core can independently work on different tasks, allowing for concurrent processing. This parallel processing capacity enhances system performance overall and speeds up operations. It is especially beneficial for undertakings that may be divided into smaller tasks and finished simultaneously.

Octa-core CPUs are best suited for computationally intensive software that requires many resources. High-definition video editing, 3D rendering, intricate scientific simulations, and virtualization are among the examples. These workloads may be effectively divided across several cores, resulting in quicker processing and shorter wait times.

Multi-Core CPUs

Multi-core CPUs, also known as multi-core processors, are kinds of computer processors that combine several independent cores onto a single chip or integrated circuit. Multi-core CPUs use two or extra cores that work collectively to execute instructions and do computations, in contrast to single-core processors, which rely upon a single core to complete all activities.

The primary advantage of multi-core CPUs is their capability to deal with numerous tasks simultaneously, improving overall performance and efficiency. The CPU’s cores perform as separate processing units that can operate independently. Due to the CPU’s ability to distribute work across its cores through parallel processing, jobs may be completed more quickly and concurrently.

Users may run numerous programs simultaneously on multi-core CPUs without suffering severe slowdowns or performance bottlenecks. For instance, each job may be given to a different core for effective processing, allowing you to browse the web, stream movies, and work on paper simultaneously. This multitasking feature makes the system more responsive overall and provides a more convenient user experience.

Multi-core CPUs excel at performing computationally demanding activities in addition to multitasking. These processors can handle complicated activities like video editing, 3D rendering, scientific simulations, and gaming more effectively by distributing the burden among numerous cores. The ability to distribute the workload across cores results in faster processing times and reduced waiting periods.