First of all, you have to make sure that the slowness problem is that the processor is 100%. Above all, it is possible for PC fans to work at high speeds and to make a lot of noise, which is a sign that the computer temperature is high, but it is important to look even at the Windows task manager (you can press CTRL + SHIFT + ESC, in the operating tab) , in fact, a 100% processor even if you do nothing.
Let's take a look below what checks you should do to solve this problem.
Look at the power supply
This problem can affect both desktop PC users and laptops. One of the signs that electricity is not working properly is that it can't provide enough power that the processor needs to operate, so the system will they automatically apply the undervolt to save electricity.
Of course, in this case, the processor will not have all its resources
To solve this on a laptop, you can go to the power settings of the machines and make sure that the selected power system is the highest performance. On a desktop PC it becomes very complicated, because the best can be change the power supply directly
Disable Superfetch (or Windows Search)
Superfetch is a Windows 10 process that allows the app to "read" our usage, looking at which apps we use most to load them into memory and next time we use them to load faster. However, this process he is always behind, and although it usually does not provide problems it is proven that can if we have old iron equipment.
If your problem is that you have a 100% processor and you have already verified that it does not come from electrical power, then disable Superfetch to make sure it is not a problem. To do this, access System Services (click start and type "Services"). In the open window, look for a service called «Sysmain«, Right-click on properties (or double-click).
In the popup window, show "Startup type" and check "Disabled." Press to accept and restart the application. It is also worth doing the same test for a service called "Windows Search".
Antivirus is well-known for its many interfaces to everything on a PC, as well as consuming many resources, so you can lose anything by disabling or disabling your antivirus to make sure this is not something the processor does. Always be 100%. Oh, and don't be afraid to "run out of antivirus", because if you are activated Windows Defender and you are not browsing suspicious web pages, you should have no problems.
Identify errors in some processes
This look will take you a long time because it's like something – it's not complicated – but it might help you to find out why the processor is 100% for no reason.
If in Windows task manager you see that a process called "Service Host" is the one that pushes the processor to 100% and you don't even know what it is, a Windows event viewer can help you Find it. To enter, press WIN + R and type "eventvwr.msc" or click the Windows button and type "Event Calculator".
Once you have it open, go to: Applications and Service -> Microsoft -> Windows -> WMI-Task -> Task. A series of events will be displayed in the central Windows column, and what we should do is look for errors.
Some errors, like the example above, are not related to any particular process, but there will be some that are there and that's what we want. In the standard error tab, which can be found by clicking on it, we can see the information called "ClientProcessID" and then the number.
We should write that number and go to the task manager. In the Details tab, we filter by «PID», and we need to find that number we saw in ClientProcessID. With this, we will have found the app that is causing the problems and can check if we can uninstall, reinstall, update or delete as we see fit. If you click the process and "Open file location" you can see where it is on disk.