Da página UEFI Wikipedia :
To ensure backward compatibility, most UEFI firmware implementations on PC-class machines also support booting in legacy BIOS mode from MBR-partitioned disks, through the Compatibility Support Module (CSM) that provides legacy BIOS compatibility. In this scenario, booting is performed in the same way as on legacy BIOS-based systems, by ignoring the partition table and relying on the content of a boot sector.
BIOS-style booting from MBR-partitioned disks is commonly called BIOS-MBR, regardless of it being performed on UEFI or legacy BIOS-based systems.
Furthermore, booting legacy BIOS-based systems from GPT disks is also possible, and such a boot scheme is commonly called BIOS-GPT.
-
A instalação do Windows inicializada a partir do EFI não permite a instalação em discos MBR e vice-versa.
-
A instalação da EFI precisa do esquema de partição EFI TO BOOT (corrija-me se estiver errado)
como:
Partition FileSystem Size Purpose
EFI FAT32 100MB EFI Boot Sector on GPT disk
MSR N/A 128MB Hidden Services Partition for GPT disk
Primary NTFS N/A Windows Installation/Data Volume contaning VHD
Mas, ele pode carregar janelas de outro disco MBR (ou VHD) no modo CSM. Então, para conseguir isso, você precisa de pelo menos dois discos, ou um disco GPT físico, contendo um disco MBR Virtual.