The BIOS is special software that interfaces. It is usually stored on a Flash memory chip on the motherboard, but sometimes the chip is another type of ROM.
1. Check the CMOS Setup for custom settings
2. Load the interrupt handlers and device drivers
3. Initialize registers and power management
4. Perform the power-on self-test (POST)
5. Display system settings
6. Determine which devices are bootable
7. Initiate the bootstrap sequence