How to perform a CPU stress test

Let’s say you bought the most powerful CPU that money can buy for your gaming needs. If you’re an overclocking aficionado, you probably outfitted the processor with a premium cooling solution to ensure high temperatures don't hold the CPU back from running at its full potential. The next step is to overclock your processor and test the stability of the ultra-fast clock frequencies.

This is where stress test applications come in handy. By subjecting your processor to extreme (and often unrealistic) workloads, these tools ensure that your system won't run into issues in the middle of your gaming session. Intel Burn Test and Prime95 are two of our favorite stress test utilities, and here's how you can use them to validate the stability of your CPU.

Before you begin stress testing

Although stress testing is a relatively safe procedure, there are a few things you should keep in mind: For starters, you should avoid running these torture tests for more than a couple of hours, especially if you’ve significantly increased your CPU voltage.

You should also stay away from the extreme modes in many stress test applications, as they can expose your CPU to even more unrealistic workloads. If your processor doesn’t have proper cooling hardware, the abnormally high temperatures from these stress tests can even damage the processor in certain scenarios.

I also advise keeping a close eye on your CPU’s clock speed and temperature during the stress tests. If the processor hits very high temperatures, it can undergo thermal throttling and reduce the clock speeds, which defeats the entire purpose of overclocking.

How to stress test your CPU with Intel Burn Test

There are plenty of stress test tools out there, but Intel Burn Test remains my preferred method to test my CPU overclock. Despite the name Intel in its title, it can also test the stability of AMD Ryzen CPUs, and it's a solid free-to-use tool for both beginners and experts.

1. Extract the IntelBurnTest.zip folder after downloading it from this link
2. Run IntelBurnTestV2.exe with administrator privileges
3. Modify the stress level and the number of threads and torture tests by changing their respective values
   
4. (Optional) Enable the Output results to results.log option if you want to make a record of the number of tests your overclock profile passed
   
5. Click on the Start button to initiate the tests
   

For most users, I recommend setting the stress level to standard or high, with the number of tests kept at the default value of 10.

How to stress test your CPU with Prime95

If you want to take the stress tests to the next level, you can go for Prime95, which offers some of the most taxing workloads for your CPU. I wouldn’t recommend it if you’re a complete beginner, as it can potentially damage your system if you run small FFT loads without adequate cooling.

1. Download the latest release of Prime95 from the official link
2. Extract the zip folder and run prime95.exe as an administrator
3. Enter the number of CPU cores and pick the type of workload for the torture test
   
4. (Optional) You can pick the Custom mode if you want to enter different values for the FFT size
   
5. Press the OK button and wait for Prime95 to finish executing the torture tests
   

How stable is your CPU?

Remember that crashes and freezes are quite common when stress testing your CPU. But unless you've subjected your processor to torture tests for hours at high voltages and temperatures, you're unlikely to damage it. That said, if you continue to encounter BSODs during the stress tests, your overclock is unstable, and it's time to turn down the clock frequency and restart the stress test.

Ideally, you should make any necessary tweaks and repeat this procedure until your processor passes the stress tests and its temperature doesn't exceed 90°C during testing. And if you're unsatisfied with your current CPU parameters, you can dial up the overclock settings and initiate an additional round of torture tests.