Clock Frequencies

The following chart shows how well the processor sustains its clock frequency, and which boost clock speeds are achieved at various thread counts. This test uses a custom-coded application that mimics real-life performance—it is not a stress test like Prime95. Modern processors change their clocking behavior depending on the type of load, which is why we provide three plots with classic floating point math, SSE SIMD code, and the modern AVX vector instructions. Each of the three test runs calculates the same result using the same algorithm, just with a different CPU instruction set.

Overclocking

For overclocking, I set a fixed voltage of 1.4 V and started increasing clocks, while checking stability at the same time. This is extremely easy because of AMD Ryzen Master, which has come a long way and is now top notch.

My highest all-core maximum stable overclock using an air cooler was 4.5 GHz. Actually, I could run everything except for some AVX tests at 4.6 GHz. That's why I settled for 4.5 GHz for all OC testing, not to give unrealistic expectations. I think most Ryzen 9 5900X's should achieve 4.5 GHz, probably slightly more.

Using a 240 mm AIO, I still couldn't get 4.6 GHz fully stable. Increasing voltage to 1.5 V pushed heat levels too high for comfort, too.