CPU vs GPU – Differences Explained

Austin
| Last Updated: July 22, 2021

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The tech world is fast evolving, and to keep pace, you must be on a constant learning process. What worked yesterday might not work today, and no one will question as long as the results also improve.

The same can be said about CPUs and GPUs. Many people did not imagine that GPUs could ever be used as browsers, and CPUs would offer better image rendering results than GPUs.

However, we went into deep research and discovered that one would work best in performing specific tasks than the other.


Read on as we unravel more about these two data processing units.

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TL;DR: CPU vs GPU

CPU

GPU

Pros

Pros

  • Completes tasks faster

  • Multi-purpose units with sequential processing to complete more tasks

  • Integrated into the computer thus works more efficiently
  • Ideal for video rendering and editing

  • Easy to upgrade

  • Compatible with almost all motherboards

Cons

Cons

  • Expensive to upgrade

  • Only works with specific motherboards

  • Generates more heat when overclocked, putting other hardware at risk

  • Discrete GPUs uses a lot of power

  • Performs limited tasks

  • Slow compared to CPUs

Best For

Best For

Multi-purpose computing where speed is a vital requirement

Video rendering, editing, and playing high-end video games

What is a CPU and How Does it Work? 

Central Processing Unit (CPU), referred to as the computer processor, is the computer’s brain that receives instructions from other hardware and software and executes them as per the commands.

The CPU (a computer chip) has dozens of protruding metal pins with electronic signals. The chip plugs into the computer's circuit board socket to aid communication between the memory and other hardware.

CPUs are multitaskers and perform many different operations at the same time. Because of the CPU, you can stream videos and listen to music while still browsing several web pages.

Inside the CPU is a combinational logic circuit called the arithmetic logic unit (ALU) that performs the actual mathematical executions received from each instruction.

ALU does this by fetching the instructions from the computer memory (RAM), executes the command, and sends the results back to memory. Many such operations happen simultaneously, thanks to the processor cores and hyperthreading that make the process possible.

For an enhanced speed by the processor, you’ll need a CPU with many cores. Each core is responsible for solving an individual problem. So, the higher the number of cores, the faster the execution process.

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On the other hand, CPUs with hyperthreading technology will enhance the speed further by multiplying the number of cores by two. A dual-core CPU with hyperthreading will have two cores plus two other virtual cores, translating to four cores.

A quad-core processor with hyperthreading will have eight cores. So, technically, hyperthreading makes your computer run an additional virtual CPU, enhancing the speed and allowing for additional task executions.

Types of CPUs

CPUs have undergone tremendous evolution since their inception in the 1970s when all computing tasks relied on a single processor. Today, we have several processors with varying levels of efficiency.

Below we list the most common types of CPUs you’re likely to encounter in the computing world.

Single-Core CPU

Single-core CPU is the oldest type of processor in the history of CPUs. It’s mostly used for personal and other official computing tasks. Just as the name suggests, this type of CPU has only one core and cannot be used for multitasking.

Executing more than one application will cause a significant decline in performance speed. One task has to complete before the next can pick up.

Dual-Core CPU

A dual-core CPU is an improvement from a single-core. It is faster and can multitask effectively by switching between two cores if more than one thread is executed.

A dual-core CPU with simultaneous multithreading technology will enhance performance further by creating additional virtual cores.

Quad-Core CPU

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The quad-core CPU is a multiple-core processor that features four cores in one CPU.  Like a dual-core CPU, quad-core will handle more workloads even better by assigning tasks to its many cores.

Quad-core CPUs will run more programs with ease without any noticeable delays when switching between tasks. It is a great processor for games and those who multitask a lot.  

Hexa Core Processor

Hexa-core processor is another multiple-core CPU with six cores and works faster than dual-core and quad-core CPUs. With multithreading technology, a Hexa core processor will complete six or more executions at the same time.

Octa-Core Processor

Octa-core processors are more advanced and with many cores to execute several programs at a go. With up to eight cores in a single CPU, this processor will perform advanced tasks more efficiently by distributing the workload to its many cores.

Octa-core processors are ideal for high-end gaming, video editing other advanced multitasking requirements.

Deca-Core Processor

Dual-core processors have two cores, quad-core comes with four cores, Hexa core with six, octa-core with eight, and Deca-core, the most advanced processor to date, has ten independent cores.

A PC or any other gadget running a Deca-core processor performs the best among all other processors in this list. Smartphone companies are already integrating this powerful CPU into their flagship phone models.

What is a GPU and How Does it Work? 

A graphics Processing Unit (GPU) is a specialized type of processor initially designed for accelerating graphics rendering. GPUs have thousands of cores and can process a lot of data simultaneously. They are great for video editing, gaming, and machine learning.

Any image display on your monitor is the work of a GPU. The screen produces millions of tiny pixels that require graphics to turn that binary data from the CPU into an image.

Some computers have inbuilt or integrated GPUs to perform the process, while others use a graphics card to render these images.

The CPU works along a software application to send information about an image to the graphics card. The graphics card then sorts these millions of pixels and decides how to use them to create an image. The information is then sent to the monitor via a cable.

Creating a 3-D image requires the graphic card to first create wireframes from straight lines. The remaining pixels are then filled via a process called rasterization before adding color, texture, and lighting.

The computer repeats this process up to about sixty times per second for fast-paced games. It is one reason GPUs have thousands of cores; otherwise, these calculation workloads would overwhelm a computer.

The graphics card uses four main components to complete the 3-D image creation process.

  •  A processor for making decisions on how to use each pixel for display

  • Memory for holding pixel information and temporary storage of completed images

  • A monitor connection for the display of the final image

Types of GPUs

Unlike CPUs that come in more than five types, GPUs are available in just two varieties: integrated GPU and discrete GPUs.

Integrated GPU

The term integrated means the GPU chip is embedded on the same chip as the CPU. Integrated GPUs have a couple of benefits that include smaller size, more cost-effective, and very energy-efficient.

Integrated GPUs also use the system RAM compared to their discrete counterparts that come with their storage.

One significant advantage of the integrated GPUs is, they don’t heat up as much as the discrete GPUs.

However, they may not perform as fast as discrete GPUs.

Discrete GPU

Discrete GPUs are standalone graphic cards that you can detach from the system at will.

These dedicated graphic cards come with separate video random access memory (VRAM) that allows fast access to image data.

However, discrete GPUs can grow very hot and also consume a lot of power.

Additionally, they are slower compared to integrated GPUs.   

Relevant Characteristics Between a CPU and a GPU

CPU

Characteristics

GPU


Few powerful cores

Cores

Thousands of less powerful cores

Handles hundreds of threads simultaneously

Threads

Handles thousands of threads simultaneously

2-3GHz

Data Transfer Speed

1GHz

Minimum 2GB (32-bit) and 4GB (64-bit)

Memory Requirements

Minimum 4GB dedicated VRAM

Sequential processing

Parallel Processing

Yes

Similarities and Differences 

GPUs and CPUs are computer processing units that may work in harmony, in other instances, independently to complete a mathematical equation. The two units share some features while still have several distinctive operational features between them.

Below we discuss the similarities and differences that exist between these two components.

What is the Difference Between GPU and CPU?

Acronym

GPU stands for Graphics Processing Unit, whereas CPU stands for Central Processing Unit.

Clock Speed

Most CPUs have between two and eight cores, although some go up to ten; for instance, we have a Deca-core processor with ten cores. CPUs are faster and with a clock speed rate of between two and three GHz.

On the other hand, GPU comes with thousands of cores that are slower compared to CPU cores. These cores can operate at a speed of about 1Ghz.

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Functionality

CPU central processing units are multi-purpose integrated circuits designed to perform multiple sequential operations.

These operations may include browsing web pages, watching movies, creating spreadsheets and word documents, playing low-stress 3D games, or other 2D-oriented games.

On the contrary, GPUs are specific-purpose circuits designed for playing high-end 3D graphic games, video rendering, and other graphics processing tasks.

Cores

While CPUs consist of just a few cores optimized for sequential serial processing, GPUs come with thousands of cores, making them very good at processing parallel tasks.

Power Consumption

Some GPU operations like video rendering are tedious and can run for more hours or even days. That translates to more power consumption compared to CPUs that complete tasks within a few minutes or hours.

Architecture

CPUs are integrated components of a computer system. While computers also have integrated graphic processing units (iGPU), most GPUs are external components that can be inserted and removed at any time.

Cost

Price ranges of CPUs and GPUs can differ depending on a few factors like the model. However, CPUs are generally expensive compared to GPUs. For instance, a high-end Nvidia Tesla GPU will cost around 10k or below, whereas a big Xeon CPU will cost a lot higher than that.

Compatibility

A CPU will only work in a specific type of motherboard. For example, a CPU intended for an Intel motherboard will not work in an AMD motherboard and vice-versa.

On the other hand, modern-day computers come with PCI Express 3.0 slots, which can accommodate just any graphics card.

Since CPUs handle most PC operation tasks apart from graphic processing, they are a vital component of a computer compared to GPUs. All PCs must have a CPU to operate, but not all will need a GPU to function.

CPU and GPU Similarities

Generally, there are a lot of differences than similarities that exist between a GPU and a CPU. Below are some notable features that the two units share.

Function

Initially, GPUs could only perform graphic processing tasks. Other computing operations like web browsing were a reserve for CPUs.

That’s no longer true. As GPUs continue to undergo evolution, there has been an introduction of General Purpose Graphic Processing Units (GPGPU) that will equally browse web pages, although at a reduced speed compared to CPUs.

Image rendering is yet another task that both GPUs and CPUs will perform flawlessly. CPUs with integrated Graphics Processing Units will render images even better compared to GPUs. However, the process is prolonged compared to GPU rendering.

Cores

While the number of cores varies sharply in CPUs and GPUs, both mathematical processes in task executions involve using cores and threads to complete various tasks.

Additionally, both CPUs and GPUs support hyperthreading technology. Hyperthreading multiplies the number of cores for more enhanced performance.

Compatibility

Although a CPU will work independently and complete its tasks perfectly, it will also work in harmony with a GPU in executing various tasks. For example, if you’re looking to speed up rendering processes while still maintaining quality, you may need to pair up a GPU and CPU.

Advantages of a CPU

 A computer system comprises many hardware and software parts that need coordination to work in harmony. The user inputs data, then the computer processes this data and outputs the results back to the user. All these are made possible by the processor.

That’s the computer's essential purpose.

Below we explore more advantages of the CPU.

A Dynamic Circuit

A computer processor contains thousands of small switches called transistors. The processor has other components that control these switches depending on the input data from an active application or computer user.

These small switches make up complex dynamic circuits like a printed circuit board (PCB) used in electronics. Through this, a computer can copy how other electronics function.

Faster Mathematical Data Calculation

Although human beings control a computer, human beings cannot match the computer’s accuracy levels once some data is fed into the system. The fast calculation of the mathematical data forms the basis as to why we rely on the computer for some tasks.

We can trust that the CPU will deliver accurate results at higher speeds from video game data processing, image editing, web browsing, and more.

Basic Computer Functionality

A CPU is the fundamental basis of a computer. All other hardware components look up to the processor to function. All the input and output from other hardware depend on the processor for data input and output.

Through the processor, you can input data and expect the output of the processed information. That explains why the processor is the computer’s brain, and all other hardware is pointless without the processor’s coordination.

Advantages of a GPU

Whether discrete or integrated, a GPU has several benefits that will help boost your computer’s performance.

Below we highlight some of the benefits

Enhanced Video Experience

Graphics cards will tremendously improve your video experience besides gaming. You’ll particularly notice this while watching high definition (HD) or Blu-ray movies.

Additionally, you can trust to have accurate video editing since graphics cards have inbuilt technology for processing and compressing videos.

Drivers Support

Graphics card manufacturers constantly release new drivers that users can download from their websites. You’ll, therefore, have good driver support whenever new games that may require operating system upgrades are released.

Efficient Memory Usage

Integrated GPUs share the system memory. Discrete GPUs, on the other hand, come with their external storage. Due to this, the computer is relieved of the burden of sharing its storage. 

GPU external storage is also speedy compared to the system's storage

Improved Computer Performance

A discrete GPU is a standalone processing unit. It uses its processor for all graphics processing tasks without depending on the CPU, which allows the CPU to concentrate on other vital tasks hence improving the computers’ general performance.

More Enhanced Gaming Experience

Most computers come with integrated GPUs to support gaming needs. However, such GPUs will not handle intensive gaming requirements. 

On the other hand, graphic cards are made purposely to enhance your gaming needs with suitable image frames at higher speeds on any gaming.  

CPU vs GPU: Which is Better?

GPUs and CPUs perform well in some specific tasks than others. Here are a few areas where you may prefer one unit over the other.

For Gaming

It is a no-brainer that gaming is one of the primary reasons you’ll need a GPU for your PC. GPU chip processors are chiefly designed to enhance graphic performance that ties directly to gaming activities.

For Video Editing

Many people attribute video editing efficiency to the GPU. As much as most graphic processes lean more on the graphics card’s quality, video editing software mainly relies on the computers’ CPU. The GPU only comes in for specific purposes, such as GPU-accelerated presets.

For Streaming

Another win for CPU is in video streaming. The CPU encodes the stream to ensure it’s shared in the streaming platform. On the other hand, GPU renders the game being played to ensure its smooth running while streaming.

For Rendering

Although a GPU has several cores that will complete the rendering process within a short time compared to the CPU, it doesn’t match the CPU in rendered image quality.

The traditional CPU-based rendering will take several hours or even days to render an image. However, the wait will be worth it as you’ll have quality and clear images free from noise.

What About TPU?

Tensor Processing Units (TPU) were first announced in 2016 after close to a year of use in Google data centers. The chip was designed specifically for Googles’ TensorFlow framework (symbolic math learning library for neural networks).

In close relation to GPUs and CPUs, TPU is a custom application-specific integrated circuit (ASIC) built to speed up the machine learning burden.

Cloud TPU was designed to maximize performance and flexibility so that developers, researchers, and businesses could construct TensorFlow compute clusters to leverage GPU, CPU, and TPUs.

High-end TensorFlow APIs support models that run on Cloud TPU Hardware.

Cloud TPUs are developed for specific types of workloads. Some machine learning workloads might need you to use GPUs or CPUs on computer engines.

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Below are TPU guidelines to help you decide on what hardware to use in your machine learning workload.

  • Large and extra-large models with extra-large batch sizes

  • Models training that runs for weeks or even months

  • Models without custom TensorFlow within the primary training loop

  • Models dominated by the matrix computations

Bottom Line

CPUs and GPUs are both necessary computing units suited for specific tasks. While GPUs will outperform CPUs in video editing, rendering, gaming, and other editing tasks, CPUs are multipurpose units that work with great speed in accomplishing many tasks at once.

Depending on what you intend to do with your machine, you may choose to invest more in one than the other.

However, keep in mind that you’ll need to find a balance between the CPU and the GPU for the two to work in seamless harmony for efficient computing.

Also, your computer will work well with just a CPU, but a GPU needs to be complemented by a CPU to work. CPUs may even give better video rendering results, although it might take abnormally long compared to a GPU.

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People Also Ask

Most computer users, especially gaming enthusiasts, confuse the importance of getting either more GPU or CPU for their computers.

Below we answer some common questions from both users looking to upgrade their systems or acquire new machines.

Can a GPU Replace a CPU?

Initially, GPUs were solely used for graphics rendering, including rapid manipulation and alteration of memory to speed up image creation.

The introduction of General Purpose Graphics Processing Units (GPGPU) has seen GPUs do more than just image rendering. These GPUs can also be used to browse web pages.

However, such GPUs are very slow and will work at about a quarter or a tenth of a CPU speed; hence, computer users cannot rely on them to perform a CPU’s tasks.

Can a CPU Run Without a GPU?

Not all computers are built for gaming. Some users just need a superfast machine for browsing tasks or carrying out other homework. That said, a computer can run perfectly without a GPU, especially if you’re not gaming.

However, since you may need to render whatever you’re computing into your monitor, you might need an integrated graphics processing unit (iGPU). An iGPU is a chip whose sole purpose is to turn data into images.

Can You Run a PC Without a CPU?

The CPU is referred to as the computers’ brain for a reason; it coordinates all the computer system activities. Just like a human being cannot operate without a brain, the same is true for a computer.

You can take out other components such as RAM or GPU. These will have minimal impact on performance, just the same way you’ll take out a human kidney, but the body will still function, although with less vigor.

Is a GPU Only for Gaming?

As much as many people will get an external graphics processing unit for gaming, modern GPUs perform more than just that. GPUs can today be used for browsing web pages (GPGPU) and also video editing. They are also valuable for 2D and 3D image rendering.



Austin

When the tech company I worked for restructured and I ended up jobless, I decided to put the wealth of knowledge and management skills to use somewhere new. I’d checked out a few buyer’s guides on the site in the past and reached out to the previous owner. A few months later, here we are. Now, I get to be behind the scenes, helping people find the best tech.