See exactly how to boot Windows7 boot sequence detailed

Do you know about the startup process of the computer? This article will elaborate on the startup sequence of the Windows operating system to facilitate the analysis and resolution of Windows startup problems.
The startup process of Windows includes the following stages:
Start the self-test phase
This stage is mainly to read the BIOS, and then the memory, CPU, hard disk, keyboard and other devices for self-test. This stage displays on the screen the print information that is self-tested.
Screen display: Print information of self-test
Initialization start stage
This stage finds the bootable bootable device, such as local disk, CD Driver, USB device, etc., according to the boot sequence specified by the BIOS, and then Prepare to boot the system from these devices.
Screen display: black screen
Boot loading stage
This stage first loads Ntldr from the boot partition (such as C drive), then Ntldr makes the following settings:
1. Built-in memory mode, if it is x86 processing And the operating system is 32-bit, set to 32-bit flat memory mode, if it is 64-bit operating system + 64-bit processor, set to 64-bit memory mode.
2. Start the file system
3. Read the boot.ini file
Screen display: Black screen, if you press F8 or multiple systems, the boot option menu will be displayed.
Detecting and Configuring Hardware Phases
This phase checks and configures some hardware devices, which are:
— system firmware, such as time and date
— bus and adapter
— Adapter
—keyboard
—communication port
—disk
—floppy disk
—input device (eg mouse)
—parallel port
—in ISA Devices running on the bus
Screen display: Black screen
Kernel loading phase
During the kernel loading phase, Ntldr will first load the Windows kernel Ntoskrnl.exe and the hardware abstraction layer (HAL). HAL is somewhat similar to embedded operations. BSP (Borad support package) under the system, this abstraction layer isolates the underlying features of the hardware and provides a unified call interface to the operating system. When the operating system is ported to different hardware, the corresponding HAL can be changed. Other kernel components are not. Need to modify, this is the usual design mode of the operating system.
Next Ntldr reads the drivers installed on this machine from HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet and then loads the drivers one by one.
After the driver is loaded, Windows does the following:
1. Create system environment variables
2. Start win32.sys, which is the kernel mode part of the Windows subsystem.
3. Start csrss.exe, which is the user mode part of the Windows subsystem.
4. Start winlogon.exe
5. Create virtual memory page file
6. Rename some necessary files (mainly driver files, if updated, need to be renamed before next reboot) < Br> Screen display: Display Windows logo interface and progress bar
Login stage
This stage will do the following:
1. Start all Windows services that need to be started automatically on the machine
2 Start local security authentication Lsass.exe
3. Display login screen
Screen display: Display login screen