If the CPU performance is required, the full CPU frequency is used automatically.
So, it is normal when the CPU is not in use that the CPU clock will be lowered to save energy.
At Intel it is the "Enhanced Speedstep" (EIST)). AMD calls the power-saving mode " Cool'n'Quiet " .
2.) What are the reasons why it fluctuates if I don't do anything?
If the maximum frequency of the CPU in the IDLE deviates or fluctuates, it may be due to the indexing (indexing) in Windows 11, 10, ..., or the Windows Defender Application Guard scans an external hard drive for ►► dangerous file types!
If this is always the same, it may be that the power saving function is deactivated!
Today's operating systems Apple's macOS, and also Windows such as Windows 11, 10 Pro, Enterprise, Home, Windows 8.1, Windows 8, Windows-Server 2019, 2016, 2012, Windows 7 Basic, Professional, Starter, Ultimate try to protect the CPU (processor) as much as possible, which is why there are fluctuations in the CPU frequency.
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