For CPU-specific virtualization capabilities, you can select Intel® Virtualization Technology or AMD® Virtualization. You must perform this step for supporting Windows® 64-bit operating systems and all guest 64-bit operating systems such as Linux.
a. If you are not in RBSU, boot the server, and then press F9 to enter RBSU.
b. Scroll down to Advanced Options, and then press Enter.
c. Scroll down to Processor Options, and then press Enter.
d. Scroll down to the supported processor (either Intel® Virtualization
Technology or AMD® Virtualization), and then press Enter.
e. At the next screen, select Enable, and then press Enter.
f. Save the configuration changes, and then exit. The server reboots.
Posted here for safe keeping. Thanks to Joe Millett for getting these instructions to me, I will post more on my home ESXi servers in due course.