Stored on the computer motherboard, solidified in the ROM chip.
Basic Input Output System (BIOS) : basic input\/output system. It is a set of programs solidified to a ROM chip on the motherboard of the computer, saving the most important basic input and output programs of the computer, post-boot self-test programs and system self-start programs, it can read and write the specific information of the system Settings from the CMOS.
CMOS is hardware, it's a writable chip. BIOS is a program that drives hardware to run software and can be upgraded. Software similar to an operating system. It is stored in CMOS. Just like the operating system is stored on the hard drive.
In terms of the capacity of the BIOS ROM chip, the capacity of the Flash ROM commonly used on the motherboard is generally 1M or 2M up to 8M. In the 486 era, only 512KBits of BIOS ROM, since the Pentium level has mainly used 1M Bits of BIOS ROM.
With more and more functions of the BIOS, more and more hardware is supported, so the program code is longer and longer, 1M Bits of capacity is no longer used, most of the motherboard uses 2M or even 8M Bits of BIOS ROM.
Extended data: BIOS is the basic input\/output system is necessary to properly boot the computer. When starting the computer, the CPU must first check whether each basic device is normal according to the BIOS chip integrated in the motherboard, graphics card and other devices, and then proceed to the next step.
By rewriting the BLOS Settings on the host computer, you can improve device performance and compatibility. Because the BIOS is so important, once the BIOS error, the consequences are quite serious.
As a bridge between hardware and operating system, BIOS can set the system operating mode and hardware-related parameters. When the system starts up, the BIOS performs a power-on self test (POST). At this point, press the Del key to enter the BIOS setup screen.
bios Settings are saved in the cmos chip on the computer motherboard, to maintain these Settings, you need power, so the motherboard will have cmos batteries, desktop computer motherboards commonly used CR2032 disposable lithium batteries, life up to 3 to 5 years.