Prime95

Testing for stability is perhaps the biggest caveat with overclocking. Unless you get too trigger-happy with raising voltages, there’s little need to worry about component failure of degradation. Stability is king, and if your CPU doesn’t want to go above a certain clockspeed or voltage, then so be it.

Prime95 likely needs no introduction for those even slightly initiated. Although its main scope is to search for Mersenne prime numbers, the tool is all but the de facto option for anyone looking to test their processor’s stability, power usage, and heat output.

While the first part of that statement is something lots of us can get behind in jest, it’s a bit of a funny coincidence that arguably the most demanding stress-test out there is all about maths.

As for how that is, there are lots of technicalities to go through. In short, the program puts your CPU through a series of FFTs, where your processor essentially has to calculate the square root of very large numbers. To that end, there are various FFT types for you to use: Smallest, Smaller, Medium, or Large. Alternatively, you may blend them all into a single stability testing gauntlet.

Custom configurations can be made if you’re more particular about your testing. Minimum and maximum FFT sizes can be set, and you may also tweak the time to run each FFT, as well as manage memory allocation for the process.

Stability is fickle when it comes to overclocking, and as it is often stated, the longer you torture-test your system, the more verifiably stable it is. Then again, what is stable to me may not be all that stable to you, hence some users take the approach of, if it doesn’t crash during my typical workloads, then it’s all good.

The Blend test is perhaps the most complete test that most users will run. Alternatively, some may opt for Small FFTs to thoroughly stress their CPU, while others will want to use Large FFTs to test out their memory.

Prime95 is a name with a lot of weight in the overclocking space, yet there’s no be all, end all solution when it comes to verifying the stability of an overclock with 100% certainty. Even so, Prime95 is a household name for good reason, so if you’re doubtful of your processor or memory’s stability, it’s never a bad idea to try it out.