This article explains the differences between a BIOS and a UEFI BIOS

Legacy Elo Windows and Intel devices utilized a standard BIOS, whereas our current devices are equipped with UEFI. The differences between these two firmware interfaces are outlined below.

BIOS (Basic Input/Output System) and UEFI (Unified Extensible Firmware Interface) are both firmware interfaces that initialize hardware and start the operating system during the boot process. However, they have significant differences in architecture, functionality, and capabilities:

1. Architecture and Design

• BIOS:

  • A legacy system that has been around since the early days of personal computing.
  • Uses a 16-bit processor mode and is limited to the first 1 MB of addressable memory.
  • Has a simple interface and a straightforward boot process that relies on MBR (Master Boot Record) partitioning.

• UEFI:

  • A modern replacement for BIOS designed to overcome its limitations.
  • Operates in 32-bit or 64-bit mode, allowing for more memory access and a more complex user interface.
  • Uses GPT (GUID Partition Table) for partitioning, which supports larger drives and more partitions than MBR.

2. Boot Process

• BIOS:

  • Follows a traditional boot sequence where it performs POST (Power-On Self-Test) and then loads the bootloader from the MBR of the boot drive.
  • Limited to booting from drives that use MBR and has restrictions on the size of the boot drive (up to 2 TB).

• UEFI:

  • Also performs POST but allows for a more flexible and configurable boot process.
  • Supports secure boot, which helps prevent unauthorized software from loading during the boot process.
  • Can boot from drives larger than 2 TB and directly from GPT partitioned drives.

3. User Interface

• BIOS:

  • Typically offers a text-based interface that can be navigated using keyboard arrows.
  • Limited in configuration options and lacks graphical capabilities.

• UEFI:

  • Provides a more advanced graphical user interface (GUI) that can include mouse support, making navigation easier.
  • Offers a more comprehensive set of configuration options, including network booting and improved hardware management.

4. Security Features

• BIOS:

  • Basic security features such as passwords to access settings, but limited in advanced security functionalities.
  • No built-in secure boot capabilities.

• UEFI:

  • Includes secure boot, which allows only trusted software to run during the boot process.
  • Supports features like measured boot and trusted boot, enhancing overall system security.

5. Compatibility and Future-Proofing

• BIOS:

  • Limited compatibility with modern hardware and operating systems.
  • Gradually being phased out as new systems increasingly adopt UEFI.

• UEFI:

  • Designed to be compatible with modern hardware and operating systems.
  • Provides a framework for future enhancements and features, making it a more sustainable choice moving forward.

Summary of Differences

In summary, BIOS is an older firmware interface with limitations in memory access, boot processes, and user interface, while UEFI is a modern, versatile, and secure firmware interface that supports larger drives, offers a richer user experience, and includes advanced security features. UEFI is the preferred choice for contemporary computing environments, ensuring better performance, compatibility, and security.