UEFI vs Legacy BIOS: What’s the Difference?
Both UEFI and Legacy BIOS are low-level software that starts when you boot your PC before booting your operating system, but UEFI is a more modern solution, supporting larger hard drives, faster boot times, more security features, and graphics and mouse cursors. T
1. Option ROM vs. Drivers
- Legacy BIOS is run by option Read Only Memory (ROM’s). The option ROMs that legacy systems run will only work if they are compatible with the hardware that is running with it. If you upgrade your hardware, you have to update the option ROMs to make sure every aspect of the booting process is compatible.
- UEFI solved this problem by
- incorporating drivers into their system in place of option ROM.
- The drivers have virtually no space limitations and are compatible with upgraded forms of hardware.
- Drivers are written separately and can be uploaded using a flash drive.
- The information uploaded onto the system is then processed by UEFI’s programming interface, which configures the data to ensure compatibility.
2. Boot Speed
UEFI’s customization capabilities affects boot time. As a result, UEFI enabled systems boot faster than Legacy BIOS systems.
3. Security
UEFI supports secure boot, which can secure the boot process by preventing the loading of drivers or OS loaders that are not signed with an acceptable digital signature. This prevents malware attacks during the boot process. Secure boot is supported by Windows 8 and 8.1, Windows Server 2012, and 2012 R2, and Windows 10 and a number of Linux distributions. SecureDoc also supports Secure boot.
Which should you use?
We would recommend the use of UEFI whenever possible for three reasons. First is the security that it provides. The second is that Intel has announced plans to completely replace Legacy BIOSes with UEFI on all their chipsets by 2020. Third is that modern OSes support and often prefer UEFI. Thus it makes UEFI the natural choice to be used whenever possible.