MAC address pass through enabled on the Latitude 7400, but IPV4 options are not available in pre-boot menu

For information on about MAC address pass through, refer to Dell Knowledge Base article What is MAC Address pass through?

To help resolve the issue, perform the following steps.

1. Reboot the computer.
2. When you see the Dell logo during POST, press the F2 key to enter the setup screen.
   Note: When the computer boots into Windows as normal, restart the process.
3. Click System Configuration, to open the options.
4. Click Thunderbolt™ Adapter Configuration.
5. On the Thunderbolt™ Adapter Configuration page, click to check the box to the left of Enabled Thunderbolt Boot Support.
6. Make sure User Authorization is selected in the options.
7. Click Apply.
8. Click Exit, confirm the changes when asked.
9. The computer will restart.
   Note: When the IPV4 options are still not available, repeat the steps, but select No Security instead of User Authorization.