It's possible to shut down Windows by software, i.e. by clicking somewhere (Start button/Shutdown), or by using tools like shutdown.exe etc.
It's as well possible to shut down Windows by pressing the power button on the computer.
What's the difference? References, hard facts?
Notes/Clarifications/Backgrounds:
- It always seemed to me pressing the power button will make Windows shut down much faster, especially with Windows XP: Computers in our corporate network running XP often took a complete minute to shut down via software, but they are always down after a few seconds when using the power button.
- I know it's possible to configure what Windows should do when the power button is pressed.
- I'm talking about pressing the power button for a very short amount of time, not holding it down for several seconds.
- An ACPI spec, page 28: "What the system does with this request depends on policy issues derived from user preferences, user function requests, and application data." But what does Windows do?
- I found a lot of conjectures and guesses while searching the internet, but I did not find any hard facts. Please do not provide more guesses, thank you.