The BIOS firmware supports both legacy BIOS and Unified Extensible Firmware Interface (UEFI). The default setting is legacy BIOS. Because some operating systems support both legacy BIOS and UEFI BIOS and some support legacy BIOS only, users have the following options:
If the operating system being installed supports legacy BIOS only, you must make sure that BIOS is set to legacy mode before you do the OS installation.
If the operating system being installed supports both legacy BIOS and UEFI BIOS, you have the option of setting BIOS to either legacy mode or UEFI mode before you perform the OS installation.
Note - The Windows Server 2008 operating systems support both BIOS modes: Legacy and UEFI, so you can choose which mode to use for the OS installation.
Note - After you have installed the operating system, if you decide you want to switch from legacy BIOS to UEFI BIOS or vice versa, you must remove all partitions and reinstall the operating system.
-> reset /System
When prompted, enter y to confirm:
Are you sure you want to reset /System (y/n)? y
Performing hard reset on /System
The BIOS screen appears.
After a few moments, the BIOS Setup Utility appears.
The Boot screen appears.