Some-things about Graphics & Video BIOS

There are two type of graphics capabilities available for Computers. External graphics and integrated graphics.

Companies like Nvidia, ATI provide External graphics cards, that can be plugged into PCIe ports of computer. Or there is lower cost option with integrated graphics available with Chipsets (such as Intel 940GM) or latest processors with integrated graphics functions (such as Intel Sandybridge processors).

For External Graphics cards, Video BIOS is stored into a flash device on the graphics card. Function of BIOS is to “boot” the graphics card. So when system is powerd on, BIOS will set the graphics function on the card such as frequency, graphics functions etc. With new graphics cards graphics chips/ GPU manufacturers such as Nvidia, ATI, use flash (“reprogram”) same chip for selling in different market segments – changing frequency/ features.

For integrated graphics capability, Intel will provide a BIOS image to its vendors (Dells, Lenovo, HP, Acer/ ASUS etc). System manufacturer (PC maker) will integrate this BIOS code as part of their standard BIOS and this BIOS will be invoked during system boot.
Once system is booted, graphics drivers take over the graphics settings and can modify the graphics settings based on displays attached/ resolution/ etc.

Overclocking enthusiasts like to play with Graphics capabilities shipped with standard BIOS BIOS (frequency for graphics chip, memory speed, etc). These enthusiasts might be able to write utilities to over-ride drivers settings.