Video BIOS is the BIOS of a graphics card in a (usually IBM PC-derived) computer. It initializes the graphics card at the computer's boot time. It also implements INT 10h interrupt and

VESA BIOS Extensions VESA BIOS Extensions (VBE) is a VESA standard, currently at version 3, that defines the interface that can be used by software to access compliant video boards at high resolutions and bit depths. This is opposed to the "traditional" int 10h BI ...

(VBE) for basic text and videomode output before a specific video driver is loaded. In

UEFI UEFI (Unified Extensible Firmware Interface) is a set of specifications written by the UEFI Forum. They define the architecture of the platform firmware used for booting and its interface for interaction with the operating system. Examples of ...

2.x systems, the INT 10h and the VBE are replaced by the

UEFI GOP UEFI (Unified Extensible Firmware Interface) is a set of specifications written by the UEFI Forum. They define the architecture of the platform firmware used for booting and its interface for interaction with the operating system. Examples ...

. Much the way the system BIOS provides a set of functions that are used by software programs to access the system hardware, the video BIOS provides a set of video-related functions that are used by programs to access the video hardware as well as storing vendor-specific settings such as card name, clock frequencies, VRAM types & voltages. The video BIOS interfaces software to the video

chipset In a computer system, a chipset is a set of electronic components in one or more integrated circuits known as a "Data Flow Management System" that manages the data flow between the processor, memory and peripherals. It is usually found on the mo ...

in the same way that the system BIOS does for the system chipset. The ROM also contained a basic font set to upload to the video adapter font RAM, if the video card did not contain a font ROM with this font set instead. Unlike some other hardware components, the video card usually needs to be active very early during the boot process so that the user can see what is going on. This requires the card to be activated before any

operating system An operating system (OS) is system software that manages computer hardware, software resources, and provides common services for computer programs. Time-sharing operating systems schedule tasks for efficient use of the system and may also i ...

begins loading; thus it needs to be activated by the BIOS, the only software that is present at this early stage. The system BIOS loads the video BIOS from the card's ROM into system RAM and transfers control to it early in the boot sequence. Early PCs contained functions for driving

MDA MDA, mda, or ''variation'', may refer to: Places * Moldova, a country in Europe with the ISO 3166-1 country code MDA Politics * Meghalaya Democratic Alliance (2018), ruling coalition government in the Indian State of Meghalaya led by National Pe ...

and CGA cards in the system BIOS, and those cards did not have any Video BIOS built in. When the EGA card was first sold in 1984, the Video BIOS was introduced to make these cards compatible with existing PCs whose BIOS did not know how to drive an EGA card. Ever since, EGA/VGA and all enhanced VGA compatible cards have included a Video BIOS. When the computer is started, some graphics cards (usually certain

Nvidia Nvidia CorporationOfficially written as NVIDIA and stylized in its logo as VIDIA with the lowercase "n" the same height as the uppercase "VIDIA"; formerly stylized as VIDIA with a large italicized lowercase "n" on products from the mid 1990s to ...

cards) display their vendor, model, Video BIOS version and amount of

video memory Dynamic random-access memory (dynamic RAM or DRAM) is a type of random-access semiconductor memory that stores each bit of data in a memory cell, usually consisting of a tiny capacitor and a transistor, both typically based on metal-oxid ...

Modding

Up until mid 2010s video ROMs were user-editable/modifiable which allowed to configure GPU features like core and VRAM clocks, or adjust fan speed curves and in certain cases a different GPU class could have been unlocked. However, nowadays both NVIDIA and AMD digitally sign video firmware, which has made it impossible to make any changes to it. Still in many cases users can flash a firmware image from another

OEM An original equipment manufacturer (OEM) is generally perceived as a company that produces non-aftermarket parts and equipment that may be marketed by another manufacturer. It is a common industry term recognized and used by many professional or ...

, thus unlocking higher performance modes or changing its mode of operation. Older NVIDIA GPUs ROMs up until the

GeForce 900 series The GeForce 900 series is a family of graphics processing units developed by Nvidia, succeeding the GeForce 700 series and serving as the high-end introduction to the Maxwell microarchitecture, named after James Clerk Maxwell. They are produced ...

could be edited using NiBiTor (NVIDIA BIOS Editor).

References

Graphics cards BIOS {{Compu-graphics-stub

Modding

See also

References