Actual difference between Quad-core & Octa-core..

Actual difference between Quad-core & Octa-core..

I wanted to write this post because I saw many people being mislead that Octa-core is twice as fast as Quad-core, but really its not. You have been mislead..

So let me clear that now..

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What are Quad-core and Octa-core processors?

Assuming that you all know what a processor is, let us dive into Octa and Quad core thing.. Quad-core is a processor having four cores & Octa-core having twice the cores of Quad-core.

What is the use of having more number of cores?

It?s just like the chefs in a Hotel, more the number of chefs less the serving time is.. Same thing applies here, more the number of cores less the time for processing your tasks such as gaming, browsing etc..

So what is the matter here? Octa-core must be faster than Quad-core due to the number of cores.. But its not.

Here comes the actual answer,

  • In case of quad-core chips, each core can be put to work simultaneously enabling fast and smooth multitasking.
  • In case of Modern Octa-core chips, they have 2 sets of 4 cores which is put to work depending upon the task difficulty.

Lets consider two sets as little CPU (lighter one ? 4 cores) and big CPU (Stronger one ? 4 cores) ? Totally Octa core (8 cores). The work is split between these two sets depending upon the task as said earlier. This type of Architecture is called big.LITTLE architecture.

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Now lets come back to little CPU and big CPU Example..

Example 1:

If you are playing a game, it is a difficult task so the stronger one big CPU takes up the task in one of its core. Simultaneously if you are using a calculator or just browsing, here the Lighter one little CPU takes the task in one of its core.

Example 2:

If you are using a calculator and browsing at the same time, these tasks are lighter so only the little CPU will be triggered not the big CPU. Even if the lighter tasks exceeds the limit, only the little CPU will be used not the big CPU.

  • Finally, regardless of the number of tasks, the little CPU will be used only for lighter tasks and Big CPU will be used only for Stronger tasks.

Now you may have a question, then what is the point of having dual-quad core (Octa core) processors?

  • It?s all for energy efficiency. Early chips used to be single core operating at lower frequencies. To increase the operating speed, they were made to operate at higher frequencies but can be increased only upto a point. This increases heat on the chip. That is why they increased the cores to reduce heat and increase the operating speed but this also has a disadvantage. It consumes power. That is why smartphones drain faster.

But that much operating speed is not necessary for most of the smartphone tasks such as navigating, messaging, browsing etc.. But gaming, video recording, animations need that speed. As speed increases, cores are needed, as more cores are used power consumption increases.

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So this is why big.LITTLE Architecture is being used. So if you have Quad-core, all the lighter and stronger tasks will be implemented in that four cores. But in Octa-core , the tasks can be separated between two sets of 4?4 cores (big CPU and little CPU). This increases efficiency a little bit higher.

This is why Octa-cores are used. So the actual difference between Quad and Octa is not on the speed but on the efficiency and power consumption. It?s just two sets of quad core squeezed in a chip as the little CPU is used for most of the tasks and big CPU for demanding tasks such as gaming, video editing etc.

So I hope you guys are clear with this, if you have any doubts comment below.

Happy processing!

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