Is it wrong to activate all the processor cores? recommendations and how to disable them

On a PC it is possible to disable or enable all the processor cores, but is it really bad or good? Surely the answer for many is obvious, but there are many users who still have doubts about the working capacity of a processor and the influence on its temperature or its durability.

So in this article we will see what this consists of activating or deactivating cores, the difference between threads and cores and if it is really recommended to layer our processor and how it is possible to do so. So, without further ado, let's begin.

Index of contents

Processors with more than one core Why?

The processor of our computer is the element in charge of carrying out all the calculations that a program or operating system generates in our equipment. The central processing unit is responsible for executing the operations that we generate after interacting with the interface of the equipment, and thanks to this the electrical signals in the form of bits of information are translated into useful work.

Well, perhaps the most significant element of a processor today is its cores in addition to its frequency. For more than 10 years, there have been processors with more than one core inside their chip, so that we understand it well, the cores of a processor are the elements that are in charge of processing the information.

A CPU with a single core consists of an ALU (Logical Arithmetic Unit), UC (Control Unit), cache memory, etc. Well, when a processor has multiple cores, all these components will be replicated in equal numbers in each core or " Core ". In this way, you will be able to perform several operations simultaneously in each clock cycle and thus multiply its performance.

So the more cores, the more processing capacity a processor will have. To this we add the frequency, the more GHz (Gigahertz), the more operations in each second it will be able to perform. This is exactly the same at AMD as at Intel, they are based on the same principle.

Difference between Core and Thread

In addition to the cores, in a processor there are threads or threads, and it is very important to know the difference between the two, because it will directly affect what we are seeing in our operating system or our BIOS.

Well, we talk about Core when we refer to a physical integrated circuit located on the processor chip. Each kernel has its own components, cache, etc. (except the shared L3 cache).

Instead, a thread or Thread is a logical kernel, a kernel that only the operating system understands exists. The operating system loads the programs for execution in memory, and also subdivides them into tasks or data control flows in order to distribute them to the processor cores. Each of these flows is called a thread and they will be perfectly managed or ordered to be processed through RAM, cache and other elements of the processor.

A processor will be able to have up to two threads per core, that is, if an i9-9900K has 8 cores, now we are going to have 16 threads in which to distribute and subdivide tasks so that processing is more efficient. Intel is capable of creating logical cores in its processors using Hyper Threading technology, while AMD does so with SMT technology. The difference is that Intel only uses it for high-end processors and notebooks, while AMD implements it throughout its Ryzen range.

When a CPU does not have any of these technologies, it will have the same number of cores as threads.

How does it differentiate between Cores and Threads?

All the previous explanation will help us to know the difference between these two elements, since deactivating cores is not the same as threading. In fact, Windows 10 is not going to present the threads as if they were kernels and obviously it is not the same to deactivate some than others. Let's see the difference in a computer with this i9-9900K inside.

The first photograph corresponds to a screenshot of the BIOS of this same computer in the section where we can enable or disable cores. As you can see, it has 8 cores (7 plus all).

Whereas, in the Windows Task Manager, Resource Monitor, we have a count of 16 CPUs, which corresponds to the threads. So keep that in mind, Windows talks about "processors" referring to threads and not cores.

In the performance section of the task manager it will be clearer to us, since here it does inform us of the number of logical processors, as it calls it.

So is it wrong to activate all the processor cores?

Definitely NOT, in fact, it is recommended and what everyone should do. If we buy an 8-core processor, the least we can do is take advantage of all its power and have all its cores active from the beginning.

Always activated by default

And it is that both Windows and other systems such as Mac or Linux, always have all the cores of a processor activated by default. Without us doing anything, whatever processor is installed, the operating system will detect all the cores automatically and give them the necessary use.

Today's systems are perfectly capable of using all cores, even processors with up to 32 cores and 64 threads such as the AMD Threadripper 2990WX. Imagine to look at that in your task manager.

Not all cores are always used

But something that we must take into account is that in systems like Windows, they may automatically deactivate cores depending on the performance needs you have. It is not common, but if we are experiencing a noticeable drop in the performance of our equipment for no reason, we may have a series of deactivated cores. Then we will see how to do all this.

Some older systems like Win dows 7 or Windows 8 do tend to disable a certain number of cores by default if they are not used, so these versions will have to be especially careful. Windows 10 for its part does not do this.

In fact, the performance of multi-core processors is completely dependent on how an application is programmed. And yes we must know that not all applications are capable of using all the cores of a processor, in fact, some only use one of them, because their programming has not considered multi-process work.

Instead, better level and quality applications, and also games are capable of using the maximum capacity of our processor, and this is how it should be.

Performance difference on a CPU with cores disabled

To make the difference between turning cores on and off a little more visual, we are going to see the comparison between a benchmark with Cinebench R15 to our Intel Core i9-9900K with all its cores activated, and with only four of them:

Well, you see, the score is cut just in half. If this happens in a benchmark, the exact same thing will happen in the used programs and in the system. Clearly, there is no point in having a CPU with cores disabled.

What's more, you may think, "At least we will have a less hot CPU because half of it doesn't work." Certainly this should be the case, although if we stress this processor with only 4 cores to the maximum, we will obtain temperatures very similar to if we did it with all of them. It is also true that the power consumption will be reduced by a few watts, but really the differences in this regard are very small and not worth it.

How to disable or enable cores on a PC

Now it is time to see how we can activate or deactivate the cores of a processor both from the Windows operating system, which most of us use, and also from the BIOS, specifically from an Asus BIOS and another from MSI.

The usefulness of this is not precisely the fact of deactivating them, but to see if our team really has all the cores in use to make the most of the power.

Disable or enable cores in Windows

This method is valid for all Windows operating systems, at least from Windows Vista.

The tool we will use will be " msconfig ", so the first thing we must do is press the key combination " Windows + R " to open the Run tool. Next, we will write the command " msconfig " to open the corresponding configuration panel.

Then we will go to the " Start " tab and click on " advanced options ".

If we want to deactivate a certain number of cores, then we will activate the “Number of processors” box and choose the number of them that we want to keep working. It is very important to know that threads will appear in this list, and not the physical cores, if your CPU has 16 threads, then to deactivate two cores we will have to choose number 12 (2 + 2 threads).

If what we want is to activate absolutely all the cores again, because we will only have to deactivate the “number of processors” box, automatically after a restart, all the cores and threads will be used.

Whenever we modify this option we will have to restart for the changes to take effect.

Disable or enable cores in BIOS

We can also do this procedure in the BIOS, although in this case, we will not be deactivating threads, but directly cores. Although it is also true that there are some BIOSes that allow the deactivation of threads.

For users who have an Asus UEFI BIOS, in most cases the process will be this: after entering the BIOS, we will activate the advanced mode and we will go to the " Advanced " section. In the options related to the CPU, we will find an option that says " Active Processor Cores ". It is here where we can select the number of cores that will be active.

It is possible that on newer boards this BIOS is somewhat different, in any case, there will always be an option, either in the advanced options of the CPU, or in the Overclocking section.

And for users who have an MSI board, the process will be similar: we will activate the advanced mode again and in this case we will go directly to the "OC" overclocking options. We will have an option whose name is exactly the same as the previous one, so there we can activate the number of cores to use.

Conclusion and related tutorials

We hope that with this little tutorial we have convinced you that the cores of a processor are for use, and not to have them disabled. There are very few advantages that we gain in temperature and consumption, and much that we lose in performance.

Now we leave you with some links that you can find interesting:

Well, if you have any problems with this matter of cores and threads, we will be happy to help you, so leave us a comment below or ask in our hardware forum.