Clock Frequencies and Boost Clock Analysis

Most modern processors feature a capability called "Boost" or "Turbo" that automatically overclocks the CPU beyond the nominal clock frequency provided certain conditions related to thread count, power draw, and temperatures are met. Our testing on this page investigates what actual real-life frequencies can be achieved in such scenarios. The data below presents the minimum, maximum, and average clock frequency of a given core/thread-count combination for a typical heavy workload. We start with one thread and go all the way up to the CPU's maximum thread count while at the same time measuring the average clock frequency for these timed testing runs.



The data above reveals that the Core i5-8500 reaches its maximum Turbo Boost multiplier of 41x (4.10 GHz) only with single-threaded workload, which is as expected. It quickly drops to 40x (4.00 GHz), which is more or less sustained throughout 2-thread, 3-thread, and 4-thread workloads, with a slight decay of 25 MHz as you go down from 2-thread to 3-thread. The processor sustains 39x (3.90 GHz) comfortably across 5-thread and 6-thread workloads. So for all intents and purposes, you can overlook the 3.00 GHz nominal clock of this chip. It's really a 3.90 GHz chip that gains 100-200 MHz at less parallelized workloads. In our testing, we found it difficult to keep the chip confined to single-threaded workload clocks as background tasks of the OS would make the chip invoke its 2-thread boost-state, which is why the maximum observed clock wasn't strictly 4100 MHz.

When not loaded at all, the processor's idle clock is 800 MHz.