This message was posted on behalf of Intel Corporation
I'm sorry for the delayed answer on this, I made some research and I think to answer to your question we need to take step back.
This Intel® Xeon® Gold 5118 processor, works at a base frequency of 2.3GHz and Max. Turbo Frequency of 3.2 GHz. The automatic process of increasing processor frequency depends on its work load and cannot be set at any given specific and fix operation frequency. Meaning there is no accurate way to perform the calculation as it will go up and down automatically.
Most likely with a given configuration, all the devices will decrease the general operational frequency at the lower device frequency. (Memory, processor, motherboard, etc.).
Also for further reference you may also check the documentation on the system you are using:
Dell PowerEdge R640 Technical Specifications
note: Intel does not endorse the usage of third party sites or documentation.
I hope this answer your question, if there is anything else I can do for you or if we're ok to set this trend as closed please let me know so we can proceed accordingly, I'll stay tuned to your comments.
Intel Customer Support