What Does “Dual Core” & “Quad Core” Mean? [MakeUseOf Explains]

intel core 2 cpu icon2   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]At one point, our computers had a central processing unit (CPU) with a single core. These days, most CPUs you’ll come across are dual core, quad core, or even octo core. We’ll explain exactly what a core is, dual core vs quad core, and how this all impacts your real-world computer usage.

The answers aren’t just helpful for leaning more about your computer — you may have to choose between a less-expensive CPU with fewer cores or a more-expensive CPU with more cores when buying a laptop, tablet, or even a smartphone. Knowing the difference between dual core vs quad core CPUs – and what it means for you – will help you make smart decisions when purchasing new hardware.

What Is a Core?

Each CPU “core” is actually a separate central processing unit, which is the part of the CPU that actually does the work. For example, a dual-core chip may look like a single CPU chip, but it actually has two physical central processing units on the chip.

Additional central processing units allow a computer to do multiple things at once. If you’ve ever used a single-core CPU and made the upgrade to a dual-core CPU, you should have noticed a significant difference in how responsive your computer is.

For example, let’s say you’re extracting an archive file and browsing the web at the same time. If you had a single-core CPU in your computer, web browsing wouldn’t be very responsive. The single core would have to split its time between web browsing and file-extraction tasks. If you had a dual-core CPU with two cores, one core would work on extracting the file while the other core did your web-browsing work. Web browsing would be much faster and more responsive.

Whether you’re doing multiple things at once or not, your computer is often doing system tasks in the background and you can benefit from additional cores to keep the operating system responsive. Applications can also be written to take advantage of multiple cores. For example, Google Chrome renders each website with a separate process. This allows Google Chrome to use different CPUs for different websites rather than using a single CPU for all browser-related tasks.

installing computer cpu on a motherboard   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]

Clock Speed vs. Cores

CPUs have a clock speed – think of it as how fast the CPU does work. (That’s actually an imperfect analogy as the truth is a lot more complicated, but it will have to do for now.)

For example, Intel’s Core i5-3330 processor has a clock speed of 3 GHz and is a quad-core processor, which means it has four cores. All four cores in this Intel i5 processor are each running at 3 GHz.

intel core i5   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]

Doubling The Cores Doesn’t Double The Speed

Many computer programs are single-threaded, which means that their work can’t be divided across multiple CPUs. They must each run on a single CPU. This means that doubling the cores won’t double their performance.

If you have a single-threaded application running on a 3 GHz quad-core CPU, that application will run at 3 GHz — not 12 GHz. It will use one core and the other three cores will sit idle, waiting for other tasks to perform.

Writing properly multithreaded applications that can scale across several CPUs at once is actually a difficult problem in computer science. It’s becoming a more crucial problem, as the future looks to be computers with more and more cores instead of fewer cores at faster and faster speeds.

Some applications can take advantage of multiple cores. Google Chrome’s multi-process architecture allows it to perform actions across several different cores at once. Some computer games can divide their calculations across multiple separate cores at once.

However, most of the applications you use are likely single-threaded. A quad-core CPU won’t run Microsoft Office twice as fast as a dual-core CPU. If all you do is run Microsoft Office, the performance might be extremely similar.

More cores help if you’re looking to do more at once or if you have a multithreaded application that can take advantage of them. For example, if you’re running several virtual machines while encoding video, extracting files, and doing other CPU-demanding things on your computer, an octo-core CPU may be able to keep up while even a quad-core CPU may stumble under such load.

Dual Core, Quad Core & More

Phrases like “dual core,” “quad core,” and “octo core” all just refer to the number of cores a CPU has:

  • Dual Core: Two cores.
  • Quad Core: Four cores.
  • Hexa Core: Six cores.
  • Octo Core: Eight cores.
  • Deca Core: Ten cores.

Controlling & Monitoring Cores

You can actually control which running programs can use a core from the Windows task manager. Right-click a process on the Processes pane and select Set Affinity.

task manager set affinity   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]

You’ll be able to select which physical CPUs (cores) the application can run on. You shouldn’t need to tweak this most of the time, although it can be helpful when you want to restrict a demanding application to certain cores or avoid bugs in old PC games.

processor affinity   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]

From the task manager, you can also use the Performance tab to view the usage of all your CPU cores.

windows task manager performance tab   What Does Dual Core & Quad Core Mean? [MakeUseOf Explains]

Hyper-Threading

Intel CPUs use a technology referred to as “hyper-threading technology.” With hyper-threading, each physical core presents itself to the system as two logical cores. In the screenshot above, we’re not using an octo-core CPU – we’re using a quad-core CPU with hyper-threading.

This improves performance to some degree, but a quad-core CPU with hyper-threading is nowhere near as good as an octo-core CPU. You still only have four physical cores, although some tricks allow them to do a bit more work at once.

Have a question of your own about how technology works? Ask us on MakeUseOf Answers! This article was inspired by several good questions on MakeUseOf Answers.

Image Credits: Nao lizuka on Flickr, Installing computer CPU on a motherboard via Shutterstock

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40 Comments -

0 votes

Akhil Kumar

Just wondering, why don’t they have a tri-core or a pent-core?

0 votes

Jumbybird

Even numbers fit better on a piece of silicon. Otherwise you have wasted space. If you have 3 cores a quarter of the chip will be empty

0 votes

null

Yes, Tri-cores are often (if not always) quad-core with one of the cores disabled.

0 votes

gupta

Don’t wondering, study I.T

0 votes

Zhong J

I have a dual core processor running at 2.3Ghz which is average for causal uses but the upper number of core is good for gaming or high demanding tasks.

0 votes

null

very few games right now take advantage of multiple cores. I’m pretty sure Battlefield 3 is one of them. In the future this will be true, but right now more cores is not much of a bonus unless your streaming or multitasking.

0 votes

BiG eViL…….

hyper threading used to be on older Pentium 4 CPUs as well, does that mean they were ‘dual core’ as well?

0 votes

null

no, hyper threading is NOT dual core. basically it can do two separate tasks at once by using different instructions but on a single core.

0 votes

Md Mukhtar Mohsin

Any way to find no. of cores in my computer ? As much as I know its i3 and 3.1 GHz.

1 votes

Tim Vels

Hi Bro,
You can check that out using Device Manager–>(open sub) Processor
and you will see how many processors are available for your system.
(example: I have a i7 so i can see 8 processors on the list)

0 votes

Md Mukhtar Mohsin

Thanks , but bad luck to me ,it shows only 2 cores.

0 votes

Colper

What I would do:

1. Start button or C: drive
2. click on “System Properties” on the top ribbon.
3. Copy and Paste the line on “Processor”. i.e. Intel Pentium 2400 @ 2.4 GHz
4. Google the line you just copied. Intel’s results should be one of the top choices. Scroll down to find all of your specs.

0 votes

Md Mukhtar Mohsin

Thanks bro but no need to google as Tim Vels told above you can see it in device manager .

0 votes

Colper

No prob. Glad you found what you were looking for. I like to google to see all the other specs and capabilities that come with the processor. Intel lays it out nicely. Cheers!

0 votes

Colper

Sorry, Forgot to mention in Step 1. Click on start Button then and/or “Computer or My Computer” depends on your OS. Then follow to “System Properties” on the top ribbon.

0 votes

Haval Abdulkarim

By the name of the CPU either it’s Dual Core (two cores) or Quad Core (4 cores) and so on.

0 votes

null

the i7 is decribed as Intel Core i7 which is not descriptive of its quad core
8 thread capability.

0 votes

Igor Rizvic

Good,thaks

0 votes

Arif Ibrahim

So, I guess the conclusion is, if you multitask a lot, go for more cores.

BTW, I heard Intel Core i3 has 2 cores, but can do 4 threads, does that mean one core can multithread?

0 votes

null

I’m pretty sure all i3’s are dual core with four threads with Hyper-threading. Each core can do two threads

0 votes

mohammadwasi786

I ever know about this, this is really important knowledge for me awesome man

0 votes

Osman Vielma

Good!
Always wanted for this explanation.
Thank you!

0 votes

Sathyanarayana Naidu

This article was just awesome. It helps normal people like me to have a better insight about the difference between the different types of core.

0 votes

Onaje Asheber

Good Stuff!!!

0 votes

Noman Fayez

nice post….

0 votes

vineedcool

what does a 4 core 4 threaded cpu mean???

0 votes

Kamruzzaman Chowdhury

Thanks for sharing these useful information. Its very helpful.

0 votes

anandarajeshwaran

There was 2 good points in this post

1)Set Affinity.– This was a good trick. Never knew I could do this
2) “It’s becoming a more crucial problem, as the future looks to be computers with more and more cores instead of fewer cores at faster and faster speeds.”

Fewer cores at faster speeds that should be the way to go.

BeginWithDisbelief.com

0 votes

Shail Hu

thanks for sucha valuable poast

0 votes

Shail Hu

*post*

0 votes

Shafiq Khan

Is there a link/site anywhere which lists the main applications such as microsoft office, adobe creative etc and shows if they support multi-threading or not?

Would be useful to know.

0 votes

Awais

Excellent information.
thanks

0 votes

kiran

good job.

0 votes

azeem

The technology which we are using today is good but the budget of some peoples are not enough to analized this latest technology so my request is the this technology should be made little cheaper inorder to make kind achievement search for some talent in this world…

0 votes

Sheriff

They say that processors are for smooth working for any application to run then why is there a RAM there? What’s the difference between a RAM and Processor?

0 votes

Sheriff

0 votes

Anwaar

Thanks for the block and providing such a wonderful information. I got my concepts cleared on Dual Core & Quad Core processors. Thanks once again.

0 votes

Ed

i AM NOT VERY CPU SAVY and hopping you guys could help. I have two computers and need to keep only one… The forst model cpu is a AMD A4-5300 dual core and the other would be an AMD A6-3620 quad core. If you had to keep one what one would it be?

0 votes

ISAH GAMBO UMAR

These advacement of technology will lead us to more multiple virtual but zero physical core, as research is carried on.

0 votes

sumbal

good