When the option is available to choose between a Legacy BIOS boot mode or UEFI boot mode operating system installation, the advantages to choosing a UEFI boot mode installation include the following:
Avoids Legacy Option ROM address constraints. For more information, see Legacy BIOS Option ROM Allocation Considerations.
Supports operating system boot partitions greater than 2 terabytes (2 TB) in size. For more information about limitations for supported operating systems, refer to Sun Blade X3-2B (formerly Sun Blade X6270 M3) Product Notes.
PCIe device configuration utilities are integrated with Setup Utility menus. For more information, see BIOS Setup Utility Screen Reference .
Bootable operating system images will appear in the boot list as labeled entities, for example Windows boot manager label versus raw device labels.
Benefits of UEFI boot mode over Legacy BIOS boot mode include:
Support for hard drive partitions larger than 2 Tbytes
Support for more than four partitions on a drive
Efficient power and system management
Robust reliability and fault management