Microsoft offers a set of tools under the banner of Sysinternals Suite that are very useful for system administrators. It contains more than a hundred different tools that offer a myriad of features. One of these tools is called “CPU Stress” and can be used to simulate high CPU usage. It is ideal if you want to see what happens when a large number of processes stress the CPU and put it under heavy load.
CPU Stress is a small portable application and can be run either as a standard user or as an administrator. When it is launched, it sets a separate thread for each of the available CPU cores. For example, if you have an octa-core CPU then it will prepare eight different threads. Even though all these threads are prepared, it runs only one of them. We can select any of these threads and choose to make them active or inactive.
We can change the thread priority from anywhere between Idle and Time Critical. Other possible values of thread priority are lowest, below normal, normal, above normal, and highest. Similarly, we can change the activity level and set it to low, medium, busy, or maximum. A higher activity level will load the CPU core with continuously running threads.
We start just by four threads, but we can keep adding more threads to load the CPU cores more. We can add a single thread at a time or we can add four new threads in just one go. It is as easy to terminate these threads as easy it is to create them. For terminating these threads, we can select them from the list and then click on the “Kill Threads” button in the toolbar or you can right-click on that thread and choose “Kill” from the right-click menu.
If you are looking for a tool that can put the entire system under heavy stress, then you can try HeavyLoad. This tool can load CPU, GPU, RAM as well as the storage media.
You can download CPU Stress from https://docs.microsoft.com/en-us/sysinternals/downloads/cpustres.