How Does a Microprocessor Work?

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How Does a Microprocessor Work

How does a microprocessor work? The microprocessor is the single component in a laptop most responsible for handling all the instructions from the hardware and software. It’s also referred to as a logic chip, central processing unit (CPU). Or simply, processor. You can feel the importance of this piece of hardware when it comes to the tasks you want to perform. With each new CPU release, laptops are becoming faster, more powerful and more efficient. Generally, the faster the microprocessor, the faster your laptop. In what follows, we’ll guide you through what a microprocessor is, what it does and more. So, if you’re ready, let’s dive in.

What is a Microprocessor?

A microprocessing unit is a silicon chip in the shape of a square or rectangle, made up of many processors. These processors are made up of millions of microscopic transistors that perform arithmetic. And logic operations including adding, subtracting, transferring numbers from one area to another and comparing two numbers. This is why the microprocessor is often referred to as the brain of a computer. It’s a programmable, multipurpose engine galvanized into motion when the laptop is turned on. On the bottom are hundreds of short, rounded metallic connector pins that plug into corresponding holes in a socket found on the motherboard. With the pin side facing down, the notched corner of a microprocessor helps guide the unit into the compatible socket located on the motherboard while a smaller lever secures it in place.

What Does a Microprocessor Do?

How Does a Microprocessor Work?

gravitasAdvantages of a Microprocessor

Microprocessors are general-purpose processing devices that can be programmed to execute a number of tasks. As such you can find them in other electronics like printers, smartphones, cars and household appliances. Here are a few reasons why they’re so ubiquitous:

  • Speed. Measured in hertz, a microprocessor with 3 gigahertz (GHz) can perform 3 billion tasks per second.
  • They can move data quickly between various memory locations.
  • Miroprocessors are so small that the same microchip can be used is in a number of applications.
  • They’re versatile. You can place the same microprocessor in any application, and it will work as long as you change the programing.  
  • They don’t consume a lot of power. Since they’re manufactured using metal oxide semiconductor technology, devices using microprocessors are much more energy efficient than the ones that use other processes.
  • Microprocessors are reliable. Since semiconductors technology are used in the production of microprocessors, their failure rate is extremely low.

Common Microprocessor Terms

Familiarizing yourself with some of the terms will help you get a better idea of what you’re looking at when you go to choose a microprocessor for your laptop. Below are some common terms related to microprocessors:

Word Length

A microprocessor’s native tongue is binary. Processors handles two types of data at any given time: data that needs processing and its program code. These are written in bits, which is a binary sequence of ones and zeros.

As you might imagine, a microprocessor doesn’t receive a constant flow of data. Instead, data is received in small chunks called bits, or a “Word.” The microprocessor is limited by the number of bits in the word, or “Word Length.” This determines the amount of information that can be processed at once during one cycle of a laptop’s internal clock. And the amount of RAM that can be accessed at the same time.

As a result, whether your laptop can run a 32-bit or 64-bit operating system (OS) depends entirely on the Word Length the microprocessor is able to handle. A 64-bit microprocessor can access more memory and a larger Word Length than a 32-bit processor. Which is why a 64-bit OS can’t run on a system with only a 32-bit processor.


Remember earlier we said that a microprocessor is made up of millions of little transistors. A bus is simply the set of conductors that transmit data or the address or control information to a microprocessor’s different elements. Most microprocessors have three different buses: the data bus, address bus and control bus.



This feature is crucial to the speed of a microprocessing unit. Cache is a type of fast memory that buffers between RAM and the microprocessor. Think of it like a temporary holding place for frequently used data. The front-side bus (FSB) of a microprocessor connects with the RAM module on the motherboard.

So, instead of relying on RAM for commonly used data. This information is stored in the microprocessor’s Cache, which is faster than RAM thanks to its physical proximity to the processor. This setup allows the processor to take requests off memory, greatly increasing a laptop’s speed.

Cache is sometimes confused with Register, which is a small amount of data storage that helps with some operations of the microprocessor. But it’s not Cache. There are three levels of Cache. Whether the processor has an L2 or L3 Cache is a reference to the speed of the on-board memory during processing. The more Cache you have, the faster your microprocessor.

Clock Speed

This is the speed at which a microprocessor can execute instructions in a second, also know as the CPU cycle. The Clock Speed of modern processors is expressed in MHz (megahertz) and GHz (gigahertz).

Once upon a time, Clock Speed (also referred to as clock rate or frequency) was a microprocessor’s most important metric. While it’s useful for determining the power of the processor, it’s not a great determination for the processing power of the laptop.

However, Clock Speed is still useful for comparing two microprocessors from the same generation. For instance, say you’re looking at two laptops with a 10th generation Intel Core i5 CPU and one is 2.2GHz while the other is 2.5GHz. The one with the 2.5GHz frequency will be a faster laptop when both are running at Max Turbo Boost.

Turbo Boost

Speaking of Turbo Boost. This is the feature that distinguishes the Intel Core i5 and i7 chips from the Core i3. This technology enables the processor to increase clock speed past its base speed whenever the need arises. Intel processors ending in “K” can be overclocked, which makes additional clock speed available all the time.


A “Thread” like “Word Length” is a stream of data. Hyper-Threading technology helps each processor core schedule and assign resources in a process called “virtualization.” Virtualization makes it so that a dual-core microprocessor operates as if it has four cores. Likewise, a quad-core CPU will work as if it has eight cores (more about cores in a moment).

NOTE: Hyper threading is only useful if the programs and applications you use are designed to take advantage of the technology. Also, physical cores perform much better than virtual cores.

Thermal Design Power

TDP is another term you’re sure to come across. Unlike, desktop microprocessors, mobile processors need to strike a balance between performance and power consumption. TDP measures the maximum power a microprocessor consumes in Watts. It’s an important metric for determining how cool your laptop will stay during intense use.

Types of Microprocessors

More cores mean a microprocessor can do more work. Multiple cores make a difference in the processing power of the laptop you choose a speed boost. But that’s only if the program you’re running is optimized to take advantage of the extra power. Below are the typical types of microprocessors you’re sure to come across:

Single Core

As a result, laptop manufacturers have added more effective cooling solutions such as heat sinks and fans to their devices.

Dual Core

This CPU has two cores that give it the performance of two CPUs.  Dual Core CPUs can handle multitasking much more efficiently than Single Core CPUs:  If you call on more than one application, it can start them at the same time instead of switching back and forth between different data streams.  But in order to take advantage of this technology, the operating system and the program running on it must have a special code written on them called SMT (simultaneous multi-thread technology)

Quad Core

These CPUs refine dual core technology.  They supersede them by adding two more cores for a total of four to the CPU design.  Quad Core CPUs allow for even greater multitasking.  But just like dual cores, unless the program the CPU is running has the SMT code written on it, you won’t feel the difference.  And, it doesn’t mean that just one request will be accomplished faster.  Rather, your laptop will feel more responsive when you start more than one request at a time.

Microprocessor Architecture

The 3 main parts of a microprocessor are the ALU, CU and memory unit. Since the 1970s, these components have become so integrated into the overall design of a processor that it’s difficult to recognize them from the outside.

So, here’s a basic diagram to clear things up:

CPU Architecture


  1. The arithmetic logic unit (ALU) performs mathematical, logical, and decision operations. 
  2. unit (responsible for addition, subtraction, multiplication and division).  And logic unit (responsible for comparing, selecting, matching and merging different data or information).  The power and efficiency of the CPU depends on the design of the ALU. 
  3. Next up is the control unit (CU) which directs all the processor’s operations.  It’s where the CPU reads and interprets requests from memory and transforms them into a series of signals (binary).  Then it sends the operation to various parts of the laptop as instructed.  The CU calls the ALU to perform the necessary calculations.  It also coordinates all input/output devices to transfer or receive instructions.
  4. The main job of the memory unit is to store data or instructions and intermediate results.  It’s divided into primary memory and secondary memory to supply data to other units of the CPU.  It allows the CPU to perform functions requested by programs like the operating system without having to ask RAM.

Another element of the microprocessor not depicted in the diagram is the transistor. These microscopic switches store binary information (ones and zeroes) to carry out calculations. They control the flow of electricity depending on whether the switch is ON or OFF. Signals turn off and on different combinations of transistors to perform calculations. A very thin silicon chip can contain several hundred million transistors.

Microprocessor Function

Central Processing Unit

As we said from the beginning, a CPU is like a very efficient calculator.  Every operation you do on the laptop has to go through this vital component.  In the process of decoding data, the CPU performs four basic steps:

  1. Fetch.  Requests are stored in memory each of which have their own address.  In this step, the processor takes the address from the program counter which is responsible for the request the CPU should execute next.
  2. Decode.  In this step, programs in need of execution are processed into Assembly code which are then decoded into binary instructions.
  3. Execute. Here, one of three things happen:  1) The CPU performs calculations with the ALU.  2) The CPU moves data from one memory location to another.  3) Or the CPU jumps to different addresses.
  4. Store. In this final step, the CPU gives feedback after executing a request before writing output to memory. 

Final Thoughts

The big takeaway here is that our desire for speedier computing devices leads to all the technological advancements we’ve seen in microprocessors. Choosing the right type of processor is important for what you expect your laptop to handle. For activities like multitasking, having more cores is like having two or four CPUs working simultaneously. Even though the microprocessor is not the overall factor in the speed and functionality of a laptop, the choices you make will affect other factors for years to come. We hope all this has given you have a better understanding of how microprocessors work so you can choose the best one for your new laptop.