Hi guys and girls,
I've already read a lot of forum articles and reddits about the mentioned problems, and also tried some of the workarounds.
I updated the BIOS / UEFI to the current version before installing Windows 1903.
I'm using a MSI X570 motherboard with the Ryzen 3900X with the stock Wraith Prism cooler.
It is connected to the correct CPU Fan 4PIN slot, without the RGB control cables.
In the BIOS hardware monitor (fan control) all values are displayed correctly (CPU temperature 38° - 40°) and the fan behaves normally.
As soon Windows booted up, it seems as if wrong temperature values would be transferred to OS. In idle state the values are jumping between 55° - 65° which causes the CPU fan to turn up and down every second. And Sometimes its stuck at ~80° in idle. And of course it gets very loud.
The CPU also has the known problem that in idle the voltage is much too high.
I don't know if the high voltage values are related to the wrong temperature values, but in my opinion 80° in idle is little high.
In addition there is the strange behavior of the cooler which is very annoying while working.
Unfortunately I am not 100% sure whether the problem is caused by the mainboard / BIOS / UEFI the CPU or Windows.
I hope you can help me.