AMI BIOS Chip: 486 ISA BIOS for Motherboards Circa 1993 28-pin 486DX AMIBIOS

Description

For Sale:
AMI BIOS
American Megatrends Chip
For 486DX ISA Motherboards
NOTE:
these are for DX Motherboards.
Unsure if they are interchangeable with SX
BIOS General Information
Basic Input Output System
. (BIOS)
All computer hardware has to work with software through an interface. The BIOS gives the computer a little built-in starter kit to run the rest of software from floppy disks (FDD) and hard disks (HDD). The BIOS is responsible for booting the computer by providing a basic set of instructions. It performs all the tasks that need to be done at start-up time: POST (Power-On Self Test, booting an operating system from FDD or HDD). Furthermore, it provides an interface to the underlying hardware for the operating system in the form of a library of interrupt handlers. For instance, each time a key is pressed, the CPU (Central Processing Unit) perform an interrupt to read that key. This is similar for other input/output devices (Serial and parallel ports, video cards, sound cards, hard disk controllers, etc...). Some older PC's cannot co-operate with all the modern hardware because their BIOS doesn't support that hardware. The operating system cannot call a BIOS routine to use it; this problem can be solved by replacing your BIOS with an newer one, that does support your new hardware, or by installing a device driver for the hardware.
Circa  1993
28-pin chip