I did a server update update and was able to move my Windows VM over and it ran perfectly.
But the VM was setup for on the old 4 core server, and I wanted to update it for my new 12 core processor. So I created a VM on the new server, and looked at its XML concerning the CPU config (topology, cores, etc.) and used that to manually edit my real VM's XML. Worked fine, but afterwards, Office 2016 complained and wanted to me to re-register. Because my licenses were OEM and tied to the machine, I had issues. Windows, also an OEM license, did not complain.
I was thinking that a VM would completely shield me from these types of issues as it would appear to use the same motherboard, chipset, etc., and this seems true it you don't touch its config, but you can run into licensing issues when upgrading a server and reconfiguring the VM to match your new CPU.
Just FYI