Boot option
Use this option to set the boot mode for the system. The following boot modes are supported:
UEFI boot mode — The UEFI boot mode is the default boot mode. It configures the server to boot UEFI‑compatible operating systems, and is required to use certain Aptio Setup Utility options.
Legacy boot mode — This boot mode configures the server to boot traditional operating systems in legacy BIOS-compatibility mode. Certain situations might require that you operate in legacy boot mode, such as booting custom OS images that were installed using legacy boot mode or created using a legacy BIOS system.