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Power outage and pc power button forcing - question


#1

Hello. Have question. Is any difference between forcing to shutdown pc by power button and power outage?


#2

TLDR: Yes

These questions were answered by the Advanced Configuration and Power Interface (ACPI) standard, which new computers have used for more than a decade. When you press the power button on your computer’s case, it doesn’t suddenly cut power — it sends a signal to the operating system and tells it to shut down. The operating system can also understand multiple types of ACPI signals, which is how some laptops are able to have separate power and sleep buttons. And, when you click Shut Down in Windows, it uses ACPI to send a signal to your computer’s hardware, telling it to cut the power so you don’t have to press the power button by hand.

That’s what happens when you press the power button.

A power outage on the other hand, sens no such signal. This is a sudden and ungraceful shutdown.


Sources


#3

So basically its the same?


#4

No, did you read my reply? The end result is the same but they are entirely different.


#5

I think hes talking about a forced power-off by pressing and holding the power button which doesn’t gracefully shutdown the OS.


#6

In that case yes. Further in the article, it does mention that.


#7

I mean forced power-off by pressing and holding the power button its the same like power outage? I mean for health for components etc .


#8

In that case I believe they are equal.

@catsay is crafting a reply, we’ll see what he’s cooking.


#9

Here’s an analogy (probably a terrible one) to how this works.

Normally if you use the Windows shutdown option or press the front power button on the case just once it triggers an ACPI shutdown event that gracefully closes all processes, cleans up after itself and powers off the machine. This is like moving out of your house and letting everyone know where you are going, saying goodbye, paying up bills etc.

If you where to shutdown the PC at the back of the case, at the wall, or encounter a power outage then the PC doesn’t have time to gracefully close open files and programs, and save things in ram to disk. This is like moving out of your house unannounced to anyone in the middle of the night leaving everything as it is and burning everything you’ve recently had on your desk (in RAM).

Holding your front PC power button in for 4 seconds until the PC is off is the same as unplugging it at the wall. As this triggers an ungraceful shutdown event (essentially a forced acpi power off event that doesn’t wait for the OS to clean up)

I hope that makes sense :smiley:


#10

:clap::clap::clap:


#11

Does the PC start shutting down as soon as you push in the power button and hold it? I would test it now, but I am busy doing stuff on this computer. Granted, it probably doesn’t give it enough time to fully shutdown before the power supply turns off, but it might be enough for open programs to exit.
Still, not recommended.
I don’t think the hardware minds losing power, it is more what the OS and software are doing at the time.