BIOS Limitations

• Bootloaders have been constrained to fit in 446 bits of the master boot record and run in 32k of system memory
• Use of the Master Boot Record has limited Addressing of Hard Drives to a shade more 2 Terabytes
• All Addressing schemes must be exactly specified for all hardware
• Used for Intel Based Hardware only
• Exposes Firmware directly creating a possible security problem
• Depends on Secondary Boot Loaders for flexible boot options