What are the cores of a processor? and the logical threads or cores?

Knowing the components of your computer well is key when assembling a good configuration. But not everyone knows that they are the cores of a processor, what difference exists between a physical and a logical core and what is the HyperThreading of Intel or SMT of AMD.

You want to know more? Don't miss our article on processor cores!

Index of contents

The central processing unit (processor) in a computer does all the work, basically running programs. But modern processors offer features like multi-core and multithreading. Some PCs even use multiple processors.

A few years ago, the clock speed of a processor used to be sufficient when comparing performance. But now things are not so simple anymore.

Now, a processor that offers multiple cores or multithreads can perform significantly better than a single-core processor of the same speed that does not offer multiple threads.

And PCs with multiple processors can have an even greater advantage. All of these functions are designed to allow PCs to more easily run multiple processes at the same time, increasing performance by multitasking or under the demands of powerful applications such as video encoders and modern games. So let's take a look at each of these features and what they might mean to you.

In this article, we review some concepts such as cores versus threads, what each one is for and what benefits the PC.

You will surely be interested in reading:

• Best processors on the market Best motherboards on the market Best RAM memory on the market Best graphics cards on the market

What is a processor?

As 99% of PC users already know, a processor is the central processing unit. This is the core component of every computer.

In other words, everything it computes has a processor inside, and it is where all calculations are performed with the help of operating system instructions.

A processor can process a single task at a time. This is not very good for performance. But there are already advanced processors that allow you to work with several simultaneous tasks and improve performance.

The old days of multiple processors

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When we talk about a processor, we are referring to a chip that is inserted into a socket on the motherboard. So, in the early days, one of these chips handled only one task at a time.

In the old days, people needed more performance from computers. At that time, the solution was to include multiple processors in one computer. That is, there were multiple plugs and multiple chips.

They would all be connected to each other and to the motherboard. Therefore, technically, better performance could be expected from the PC. This was a fairly successful method until people discovered the downsides.

• It was necessary to provide a dedicated power supply and installation resources for each processor. Because they were different chips, the latency for communication was too high. This wasn't really a good performance thing. One set of processors could produce a lot of heat in the long run. So it would take a lot of resources to deal with the extra heat.

Dual Socket Server Motherboard

This required a motherboard with multiple processor sockets. The motherboard also needed additional hardware to connect those processor sockets to RAM and other resources. And that was how the concepts of multithreading and multicore entered the scene.

Currently, most computers only have one processor. That single processor can have multiple cores or HyperThreading technology, but it's still just a physical processor inserted into a single socket on the motherboard.

Multi-processor systems are not very common among today's home user PCs. Even a high-powered gaming desktop with multiple graphics cards will generally only have one processor. But it is possible to find systems with multiple processors in supercomputers, servers and high-end systems that need maximum power for complex tasks. In these times, having a team with several processors will be much less efficient than it seems, since there are very fast processors and many cores for home users like the i9-7980XE.

Multiple cores in one processor

The idea of ​​connecting different processors was not really good for performance. Then the idea came up to have two processors inside a single chip.

Therefore, as a way to take an effective step towards performance, manufacturers included multiple processors in a single processor. These new units were called nuclei.

From now on, these processors were called "multi-core processors". In this way, when the operating system analyzed the computer, it encountered two processors.

Rather than dedicating the storage and power supply to separate chips, multi-core processors did the work of extra performance.

Of course, there were other advantages, too. Because both processors were on the same chip, the latency was lower. This helped improve communication and speed. Currently, you can see a wide variety of multicore processors on the market.

For example, in dual-core processors there are two processing units. And if we put it into practice, in the case of Quad Core processors we find 4 processing units.

Unlike multithreading, there are no tricks here: A dual-core processor literally has two processors on the chip. A quad-core processor has four central processing units, an eight-core processor has eight central processing units, and so on.

This helps to dramatically improve performance while keeping the physical processor small to fit in a single socket.

There just needs to be a single processor socket with a single processor inserted into it, not four sockets with four processors, each of which needs its own power, cooling, and other hardware. There is less latency because the cores can communicate more quickly since they are all on the same chip.

Intel HyperThreading

Parallel computing has been in the industry for a while. However, it was Intel who brought the benefits of it to personal computing. And there it was called Intel Hyper-Threading Technology.

Intel's Hyper-Threading technology makes your operating system believe there are multiple processors; in fact, there is only one. It is a kind of pretense to improve performance and speed.

HyperThreading was Intel's first attempt to bring parallel computing to consumer PCs. It debuted on desktop processors with the Pentium 4 HT in 2002.

Those Pentium 4s had a single core, so they could only perform one task at a time. But HyperThreading appeared to compensate for that. With this Intel technology, a single multithreaded physical core appears as two logical processors in one operating system. The processor is still one, so it's a bit of a dummy. While the operating system sees two processors for each core, the actual processor hardware only has a single set of execution resources for each core.

Thus, the processor pretends to have more cores than it has, and uses its own logic to speed up the program's execution. In other words, the operating system is tricked into seeing two processors for each core.

At that time we set up a Pentium 4, which the boy from the store nicknamed him as the "NASA PC". What a good times!

HyperThreading allows the two logical cores of the processor to share physical execution resources. This can speed things up a bit: if one virtual processor is stuck and waiting, the other virtual processor can borrow its execution resources. HyperThreading can help speed up the system, but it's not as good as having real additional cores.

Fortunately, multithreading is now a "bonus". While the original consumer processors with HyperThreading only had a single core that disguised itself as multiple cores, modern Intel processors now have both multiple cores and HyperThreading technology.

A dual-core processor with multithreading appears as quad-core in the operating system, while a quad-core processor with HyperThreading appears as having eight cores.

Multithreading is not a substitute for additional cores, but a dual-core processor with HyperThreading should perform better than a dual-core processor without HyperThreading.

The hardware execution resources will be divided and ordered to give the best speed to multiple processes. As you can see, the entire work is virtual. This HyperThreading can often offer a 10-30% performance boost on the task being run. AMD also has this technology but instead of HyperThreading it calls it SMT. Does it work? Is the same.

Are multiple cores and threads worth it?

If your computer has a multicore processor, it means there are multiple CPUs. It also means that it can have better performance than a single core processor.

And if we talk about HyperThreading, a single-core processor with this technology will work better than one of these processors that lacks this multitasking technology.

On the other hand, that a processor is multithreading is something virtual. In this case, the technology uses additional logic to manage multiple tasks. Due to this, the total performance will not be really visible. So, if you really want to compare a single-core processor or a multi-core processor, we can affirm that the latter are always better. Games like Battlefield or multiplayer always offer better performance with a processor with multiple logical cores in areas with many explosions.

What did you think of our article on what are the cores of a processor ? Did you find it interesting? Are you missing something?