BIOS

The BIOS (Basic Input/Output System) is a essential firmware located on a computer’s motherboard. Its main function is to initialise and test the system’s hardware during the boot process and to provide runtime services for operating systems and programmes. The BIOS is the first piece of software to run when a computer is switched on, and its code is stored on a ROM (Read-Only Memory) chip on the motherboard. 

What is the BIOS used for? 

The BIOS has several crucial functions that enable a computer to operate correctly. Here are some of the things we can change using it: 

• Hardware configuration: The BIOS allows you to configure and manage the system’s hardware components, such as the processor, the RAM, hard drives and optical drives. 

• Boot order: We can change the boot order of the devices, which determines which device the operating system will start from (for example, a hard drive, a USB drive or a CD/DVD). 

• Peripheral settings: The BIOS allows you to enable or disable built-in peripherals such as USB ports, network cards and sound cards. 

• Performance settings: We can adjust settings such as the processor and memory clock speeds, which can improve system performance. 

• Security: The BIOS allows you to set passwords to protect access to the system and to the BIOS settings themselves. 

How does the BIOS work? 

To understand how the BIOS works, it is useful to know how a computer boots up: 

• Power: When the computer is switched on, the processor executes the BIOS code from the ROM chip. 

• POST (Power-On Self-Test): The BIOS carries out a series of tests to check that essential hardware (such as RAM, the keyboard and the graphics card) is working correctly. 

• Hardware initialisation: The BIOS initialises and configures the hardware components according to the settings stored in the CMOS (Complementary Metal-Oxide-Semiconductor), a small memory chip that stores the BIOS settings. 

• Load the boot loader: Once the hardware has been initialised, the BIOS searches for a boot loader on the primary boot device (for example, the hard disk) and hands control over to it. 

• Operating system start-up: The boot loader loads the operating system into memory and starts it running. 

Problems with the BIOS 

Although the BIOS is essential for a computer to function, a number of problems can arise in connection with it: 

• Update failed: Updating the BIOS can be risky. If the update fails, it may render the computer inoperable, as a corrupted BIOS will be unable to initialise the hardware. 

• Incorrect configuration: Changing the BIOS settings incorrectly can cause boot problems or system instability. For example, setting the processor clock speed incorrectly can lead to overheating. 

• Hardware compatibility: Some BIOS versions may not be compatible with certain hardware components, which may cause recognition or performance issues. 

• Forgotten passwords: If you set a password in the BIOS and forget it, it may be difficult to access the BIOS settings or even boot up the computer. 

• POST errors: If the BIOS detects a problem during the POST, it may emit a series of beeps or display error messages indicating which component is faulty.