I've learned the difference between UEFI and BIOS, and it seems that BIOS only boots MBR hard drive while UEFI only boots GPT hard drive. And UEFI cannot boot normal USB flash drive so I have to make the USB flash drive "UEFI-bootable". What is the difference between normal USB drive and "UEFI-bootable" drive? Is it true that a normal USB drive uses MBR while a UEFI-bootable one uses GPT? Can I boot a UEFI-bootable USB flash drive on an old PC with only legacy BIOS support?
A “UEFI-bootable” USB flash drive and can I boot it on legacy BIOS
biosgptmbruefiusb-boot
Related Question
- Installing Win 7 To GPT and Why My UEFI Mobo Won’t Boot From CD Unless In Legacy Mode
- Configuring UEFI dual BIOS to boot from SSD and access a secondary HDD
- Why arcane legacy steps to boot from USB with GPT and UEFI
- Determine if BIOS supports UEFI (and GPT)
- Can’t create bootable USB drive: Rufus hangs after writing MBR
- How to boot from a USB flash drive with Alienware Aurora R7
- GPT drive not showing up as UEFI in bios
Best Answer
Most UEFI implementations can also boot from MBR-partitioned USB drives. They expect a file at
/efi/boot/bootx64.efito exist. For best compatibility, using the FAT32 filesystem is highly recommended.An additional BIOS bootcode may exist on the drive. It will be ignored by UEFI.
Bottom line: Hybrid bootable USB drives are possible and do exist.