Search results
Results from the WOW.Com Content Network
BIOS POST card for ISA bus BIOS POST card for PCI bus Professional BIOS POST card for PCI bus Two POST seven-segment displays integrated on a computer motherboard. The original IBM BIOS made POST diagnostic information available by outputting a number to I/O port 0x80 (a screen display was not possible with some failure modes). Both progress ...
After the motherboard BIOS completes its POST, most BIOS versions search for option ROM modules, also called BIOS extension ROMs, and execute them. The motherboard BIOS scans for extension ROMs in a portion of the " upper memory area " (the part of the x86 real-mode address space at and above address 0xA0000) and runs each ROM found, in order.
An option ROM for the PC platform (i.e. the IBM PC and derived successor computer systems) is a piece of firmware that resides in ROM on an expansion card (or stored along with the main system BIOS), which gets executed to initialize the device and (optionally) add support for the device to the BIOS.
BIOS interrupt calls perform hardware control or I/O functions requested by a program, return system information to the program, or do both. A key element of the purpose of BIOS calls is abstraction - the BIOS calls perform generally defined functions, and the specific details of how those functions are executed on the particular hardware of the system are encapsulated in the BIOS and hidden ...
While many of these systems still allow booting only the BIOS-based OSes via the Compatibility Support Module (CSM) (thus not appearing to the user to be UEFI-based), other systems started to allow booting UEFI-based OSes. For example, IBM x3450 server, MSI motherboards with ClickBIOS, HP EliteBook Notebook PCs.
Computer systems such as laptops often produce large amounts of heat which must be dissipated. This is typically done by activating a fan to blow air over the components that are producing heat; the fan is not simply turned on or off, but is driven at high speed by the embedded controller for a short time and then left running at low speed ...
AMIBIOS (also written as AMI BIOS) is the IBM PC-compatible BIOS that was formerly developed and sold by American Megatrends since 1986. [10] In 1994, the company claimed that 75% of PC clones used AMIBIOS. [16] It is used on motherboards made by AMI and by other companies. [3] A chip containing an old version AMIBIOS image, pulled from an ECS ...
For this reason, later BIOS implementations may use a small portion of BIOS flash ROM as NVRAM, to store setup data. [7] Today's UEFI motherboards use NVRAM to store configuration data (NVRAM is a portion of the UEFI flash ROM), but by many OEMs' design, the UEFI settings are still lost if the CMOS battery fails. [8] [9]