Hello   Throttling the CPU is not a C state. C states are idle states. If the CPU frequency is above 0 it is not a C state. The ACPI driver within the operating system controls P states. The maximum CPU frequency may be throttled by the system board in certain situations. If 2.2 GHz is the maximum rated frequency of the CPU then this issue is software related. If the maximum frequency of the CPU is higher than 2.2 GHz but the OS is showing it is limited to 2.2 then then system board is throttling it for some reason, most likely due to inadequate power or a CMC or iDRAC not working properly. Thanks
Hi,  We've got a strange problem with one of a blades in VRTX chassis. It's set to a performance profile in BIOS, windows 2016 is set to high performance, but CPU is behaving like C states were not turned off. It jumps from 0.17Ghz to 2.20Ghz depending on system load.  Firmware, bios and drivers are updated to the latest versions. Any help would be greatly appreciated. Regards, Marcin 
poweredge m620 CPU throttling