Hyper-V and Processor power states on Windows server 2012 (Intel Speedstep)

Hi,

I have recently added the Hyper-V role to my server running Windows Server 2012 and found that under power options I can no longer control the minimum and maximum processor states. The processor constantly runs at its maximum frequency

If I remove the Hyper-V role then the processor state options return.

Is this by design or a bug?

Is there a way to force the return of the processor state options? (it's the same across all 3 power plans)

Thanks!