26 Facts About BIOS flashing

The BIOS flashing firmware comes pre-installed on an IBM PC or IBM PC compatible's system board and exists in some UEFI-based systems too as a compatibly support module to maintain compatibility operating systems that do not support UEFI native operation.

Originally, BIOS flashing firmware was stored in a ROM chip on the PC motherboard.

In later computer systems, the BIOS flashing contents are stored on flash memory so it can be rewritten without removing the chip from the motherboard.

BIOS flashing uses the boot devices set in Nonvolatile BIOS flashing memory, or, in the earliest PCs, DIP switches.

At boot time, all BIOS flashing services are available, and the memory below address 0x00400 contains the interrupt vector table.

Related searches

Motherboard BIOS flashing typically contains code for initializing and bootstrapping integrated display and integrated storage.

Once an option ROM returns, the BIOS flashing continues searching for more option ROMs, calling each as it is found, until the entire option ROM area in the memory space has been scanned.

BIOS flashing ROM is customized to the particular manufacturer's hardware, allowing low-level services to be provided in a standardized way to programs, including operating systems.

Since the AT-compatible BIOS flashing 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 flashing services.

In modern PCs running modern operating systems the BIOS flashing interrupt calls is used only during booting and initial loading of operating systems.

The BIOS flashing contain patches to the processor microcode that fix errors in the initial processor microcode; microcode is loaded into processor's SRAM so reprogramming is not persistent, thus loading of microcode updates is performed each time the system is powered up.

Some BIOS flashing implementations allow overclocking, an action in which the CPU is adjusted to a higher clock rate than its manufacturer rating for guaranteed capability.

BIOS flashing interrupt calls are not used by modern multitasking operating systems after they initially load.

Since 2010, BIOS flashing technology is in a transitional process toward UEFI.

Early BIOS flashing versions did not have passwords or boot-device selection options.

The BIOS flashing was hard-coded to boot from the first floppy drive, or, if that failed, the first hard disk.

In modern PCs the BIOS flashing is stored in rewritable EEPROM or NOR flash memory, allowing the contents to be replaced and modified.

Original IBM PC BIOS flashing was stored on mask-programmed read-only memory chips in sockets on the motherboard.

The effect of the publication of the BIOS flashing listings is that anyone can see exactly what a definitive BIOS flashing does and how it does it.

In May 1984 Phoenix Software Associates released its first ROM-BIOS flashing, which enabled OEMs to build essentially fully compatible clones without having to reverse-engineer the IBM PC BIOS flashing themselves, as Compaq had done for the Portable, helping fuel the growth in the PC-compatibles industry and sales of non-IBM versions of DOS.

New standards grafted onto the BIOS flashing are usually without complete public documentation or any BIOS flashing listings.

Former major BIOS flashing vendors included American Megatrends, Insyde Software, Phoenix Technologies, Byosoft, Award Software, and Microid Research.

BIOS flashing Meningitis has relatively harmless, compared to a virus like CIH.

Second BIOS flashing virus was CIH, known as the "Chernobyl Virus", which was able to erase flash ROM BIOS flashing content on compatible chipsets.

Third BIOS flashing virus was a technique presented by John Heasman, principal security consultant for UK-based Next-Generation Security Software.

Related searches

Researchers Anibal Sacco and Alfredo Ortega, from Core Security Technologies, demonstrated how to insert malicious code into the decompression routines in the BIOS flashing, allowing for nearly full control of the PC at start-up, even before the operating system is booted.