Boot Process
Step 1 - Power Good
You turn the computer on.
The power supply is going to taste the power and make sure everything is OK.
Step 3 - POST
BIOS starts the Power On Self Test (POST)
Step 5 - Loading Drivers
BIOS loads very basic drivers for devices attached to the computer into system memory.
Step 7 - Video
POST launches video display
It uses very basic video settings
This is the first time in the boot process anything is displayed on the monitor.
Step 9 - The Handoff
POST hands off to a process called the bootstrap loader
Step 2 - The CPU wakes up
Power supply then wakes up the CPU.
The CPU is brought into the boot process.
CPU is going to activate the BIOS.
BIOS is a very basic understanding how computer hardware is supposed to work.
BIOS doesn't care about the make and model.
Step 4 - BIOS and CMOS
BIOS talks to CMOS
BIOS and CMOS communicate to make sure everything is there where it is supposed to be.
Step 6 - System Bus
The BIOS will have CPU send signals over the system bus to make sure all basic components are working.
Step 8 - Memory
The POST writes and reads from the systems RAM
Step 10 - Bootstrap Loader
Loads operating system from the bootstrap loader.