The BIOS (Basic Input Output System) is a software program stored on the motherboard, independent of the operating system your laptop is running.
It is responsible for auto-configuration on power-up, and is therefore the very first program to run when a computer starts up. It's like the backbone of your PC.
You may need to configure the BIOS if your computer has a bug, or if you want to access certain settings. So how do you find and use the BIOS?
What is the purpose of a PC's BIOS?
Your computer's BIOS is stored both on a small read-only memory chip (ROM) and on another RAM chip (EEPROM). Parameters installed on ROM cannot be modified, whereas those on EEPROM can be changed by flashing.
The BIOStells the computer how to perform basic functions such as booting and keyboard control. It is also used to identify and configure a PC's hardware, such as the hard disk, CPU, memory and other associated equipment.
In addition to booting the operating system, it also acts as a system tester and configurator.
The BIOS supports several hardware configuration options that can be modified via the configuration utility. Saving these changes and restarting the computer applies the modifications to the BIOS and changes the way the BIOS instructs the hardware to operate.
The four main BIOS functions
Going to your PC's BIOS gives you access to four main functions.
1. POST (Power-On Self-Test): This function tests hardware, memory and ensures that no errors exist before loading the operating system.
2. Bootstrap Loader: This function locates the operating system. If a compatible operating system is located, the BIOS will pass control to it.
3. BIOS Drivers: Low-level driver management that gives the computer basic operational control over your computer's hardware.
4. BIOS configuration or CMOS configuration: Configuration program that allows you to set hardware parameters, including system settings such as computer passwords, time and date.
Common BIOS actions
In most BIOS systems, you can also perform a number of common actions, such as :
- Change boot order
- BIOS update (flashing)
- Modify hard disk parameters
- Modify CD or DVD drive settings
- Display the amount of memory installed
- Enable or disable power-on self-test (POST)
- Modify processor parameters
- Modify memory parameters
- Modify system voltages
- Enable or disable RAID
- Enable or disable integrated USB card
- Enable or disable integrated audio
- Modify fan speed and fan speed settings
- Display processor and system temperatures
- Display system voltages
All BIOS options are configurable via the BIOS Setup Utility.