BIOSsupported

BIOSsupported is a designation used to indicate compatibility with the Basic Input/Output System, the firmware interface used by IBM PC-compatible computers. It denotes that hardware or software can boot and operate using BIOS services rather than the newer UEFI interface. In practice, BIOS-supported components are designed to work with legacy BIOS calls and boot sequences.

Historically, BIOS has been the standard firmware interface since the early IBM PC era. In recent systems, UEFI has largely replaced BIOS, but most modern motherboards offer a Compatibility Support Module (CSM) that provides BIOS compatibility to support older operating systems and bootloaders.

In hardware terms, BIOS-supported means the device implements BIOS interrupt services (such as INT 10h for video and INT 13h for disk) and can boot from a disk that uses the Master Boot Record (MBR) scheme. It may also rely on real-mode operation and restrict memory use to conventional limits. In software terms, BIOS support enables installation and execution of operating systems or bootloaders that require legacy BIOS interfaces.

Modern contexts often label devices as BIOS-supported when they can be configured to boot in Legacy BIOS/CSM mode in addition to native UEFI mode. This dual capability facilitates backward compatibility for older operating systems and certain virtualization environments, while also exposing security trade-offs inherent to legacy boot processes.

See also: BIOS, UEFI, CSM, MBR, GPT, Secure Boot.