This message was posted on behalf of Intel Corporation
I understand that you are having problems adjusting the voltage of the processor the way you desire by using Intel ® Turbo Boost Max and also Intel ® XTU.
First, I would like to start by saying that Intel ® Turbo Boost Max does not support your unit, it is not under the list of supported processors. Another thing is that your processor is not an unlocked processor, this means that the processor cannot be modified when it comes to voltage or frequency so that is the reason why you are unable to keep the processor running with that voltage.
Attached is a list of the processors that support Intel ® Turbo Boost Max for reference.