Voltage and frequency on the I5-6600K processor - are the readings normal?

Question

Intel

Hello! I'm trying to overclock the i5-6600K. I raise the frequency, then I run a mixed test in Prime95 and raise the voltage until there are no errors.
Empirically established that in order to achieve a frequency of 4.3 GHz, it is necessary to raise the voltage to 1.26V. For 4.4 GHz, the threshold is already higher - at least 1.29V is required. 4.5 GHz is taken at 1.30V without any problems. I haven’t tried it further, there is no need for a very extreme overclocking.
Question: Are these indicators normal? I read on reddit that for some, overclocking 4.3 is achieved without raising VCore at all, at a level of 1.18V. It is clear that this is all individual, but I am interested from personal experience - how normal is this for this particular model, and is it safe to leave it with a voltage of 1.26V and a frequency of 4.3? At the same time, the temperature in the stress test does not rise above 75 degrees, on average - 66.