Windows Power Management is a feature that works with CPUs that can dynamically adjust processor voltage and core frequency to decrease heat and power usage.
As you can see in Task Manager, while the Maximum Speed is 2.30 GHz, the actual speed is typically much lower ~1.0 GHz.
However, installing Hyper-V feature, it seems that the Processor Power Management doesn’t appear to work anymore
Processor power management is still running but when the hypervisor is enabled, it
is in charge of managing processors, including processor power
management. Therefore, you won’t see Processor Power Management activity
when looking at Task Manager or the root’s (parent) performance counters. You
have to look at the hypervisor logical processor counter sets to see C-states,
Take a look at this article about Hyper-V Logical Processor Counters.