where is the bios stored in a computer
BIOS
Operating systems and executive software that are designed to supersede this basic firmware functionality provide replacement software interfaces to application software . Applications can also provide these services to themselves . This began even in the 1980s under MS - DOS , when programmers observed that using the BIOS video services for graphics display was very slow . To increase the speed of screen output , many programs bypassed the BIOS and programmed the video display hardware directly . Other graphics programmers , particularly but not exclusively in the demoscene , observed that there were technical capabilities of the PC display adapters that were not supported by the IBM BIOS and could not be taken advantage of without circumventing it . Since the AT - compatible BIOS ran in Intel real mode , operating systems that ran in protected mode on 286 and later processors required hardware device drivers compatible with protected mode operation to replace BIOS services .
Operating systems and executive software that are designed to supersede this basic firmware functionality provide replacement software interfaces to application software . Applications can also provide these services to themselves . This began even in the 1980s under MS - DOS , when programmers observed that using the BIOS video services for graphics display was very slow . To increase the speed of screen output , many programs bypassed the BIOS and programmed the video display hardware directly . Other graphics programmers , particularly but not exclusively in the demoscene , observed that there were technical capabilities of the PC display adapters that were not supported by the IBM BIOS and could not be taken advantage of without circumventing it . Since the AT - compatible BIOS ran in Intel real mode , operating systems that ran in protected mode on 286 and later processors required hardware device drivers compatible with protected mode operation to replace BIOS services .