I recently bought a new motherboard (Gigabyte Z390 Gaming SLI) and noticed that it makes some noise when the CPU is idle and the core voltage changes from 0.650 V to 1.2V. But this noise disappears when the CPU is under load and the core voltage is kept at level 1.1-1.2V. Therefore, I manually set the CPU core voltage to 1.2V in UEFI (all other voltage settings are left in Auto). Now there is no noise, and the core voltage is always 1.2V (in idle mode or under load), but I'm not sure that this is safe for the CPU and will not reduce its lifetime.
Thank you for posting on the Intel® communities.
It's worth mentioning that when the voltages of the processor are being manipulated it carries several risks since the processor could start to work outside of the parameters that Intel tests and validates.
For your future reference, It's important to mention that altering clock frequency or voltage may damage or reduce the useful life of the processor and other system components and may reduce system stability and performance. Product warranties may not apply if the processor is operated beyond its specifications.
Regarding the sound, it would be good to check that out with the system manufacturer of the motherboard as well just in case the could be related to the motherboard or the system might need a BIOS update to run properly.