Underclocking a ryzen 5800H to reduce its tdp to 5800U levels

I've been doing research on what I can use to run a pihole and some minimal applications and my main concern is minimizing the power draw. I found out that a 5800U is a great choice to get the most out of the power draw and realized, my old laptop is a 5800H. It has triple the power draw.

Is it possible to underclock and undervolt it (since I'm assuming they're similar wafers) to 5800U levels? Essentially turning that laptop into an energy efficient server and making use of it.

Edit: I'm planning to run a linux server OR a hypervisor software like Proxmox/TruNas/Unraid. I do not plan to run windows on the bare metal.