What is Partial Boot?

The normal (full boot) is a boot up of your PC from switched off state to the Windows desktop.

In addition to the normal boot up process there 3 other ways to get to the Windows desktop:

  1. Logon after logging off.
    If you log off from your account and log on again, the Windows will close your desktop and user′s processes and load them again.
    BootRacer will count the time from logon moment till the desktop ready moment.
    Of course, this time is smaller than the full boot time.
    To avoid misunderstanding, BootRacer gets approximate time to logon from the latest previous full boot.
    You could not compare approximate time with a full boot and use it for contest.
    But it′s may be useful for monitoring system activity on your PC.
  2. Boot from kernel hibernate (fast startup). "Fast startup" is a boot from kernel hibernate state.
    During shutdown Windows logs off a user, closes the user′s processes and save the system to the hibernate file.
    Next time after switch on signal Windows first restores the system from hibernate file, next user logs on as usual.
    It′s incorrect to compare the normal boot time with restoring from hibernate time.
    Sometimes "Fast Startup" is able to boot your Windows faster, sometimes not.
    But if you want to check measure a full boot time, you need to reboot your PC. Because "fast startup" works only if you use Windows shutdown button.
  3. Boot from hibernate state. You will boot from the saved hibernate file directly to the desktop. All user′s processes and windows are restored too.
    BootRacer does not measure boot from hibernate state.

Difference between Cold Startup and Fast Startup:

Normal (Cold) Startup Fast Startup

All Windows versions

Only for Windows 8/8.1/10
System starts after full shutdown or reboot System starts after hybrid shutdown.
(Hybrid shutdown: logs off all users, prepares for hibernation, saves the kernel memory image in Hiberfil.sys and shuts down the computer)

System Loading
Boot loader constructs a kernel memory image by loading the sections of the Windows kernel file into memory and linking them. Next, the kernel configures core system functions, enumerates the devices attached to the computer, and loads drivers for them.

Restore kernel from Hibernate
Fast startup simply loads the hibernation file (Hiberfil.sys) into memory to restore the previously saved image of the Windows kernel and loaded drivers.
Welcome screen/User Logon Prompt

BootRacer Time To Logon = X sec

BootRacer Time To Logon = Unmeasured
BootRacer displays approximate logon time from previous full boot.
Boot to Desktop
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