Can a hard shutdown cause damage?

Hello folks.

I have some questions here, generally revolving around the concept of a "hard shutdown" of a desktop PC. That is, terminating a session in some manner other than using the build in software "shut down" option in an OS. Just for my own curiosity.

There are two notable methods of doing this that come to mind:

1. Power off. On most modern computers, pressing and holding in the power button for X amount of seconds, after which the machine turns off. I notice that when this is done, the OS often initiates it's own software shutdown procedure, which is generally cut short.

2. Power cut. Power to the machine is abruptly stopped, in many possible manners such as just pulling the plug out.

I've often heard stories and urban legends about doing these things and how they're bad, but I'd really like to seperate truth from fiction. A little bit of googling has turned up far too much noise to signal, with answers along the lines of "I've been doing it for years with no problems so it must be fine" or "my teacher said not to do it so it's bad".

I'm looking for true, cited, and verifiable facts, about the following:

1. Can doing either of these actions, cause damage to hardware? What types of hardware could be affected, and in what ways ? particularly, does it pose a risk to hard drives or power supplies?

2. Can either of these actions damage an OS or a filesystem? Under what conditions might file corruption occur with hard shutdowns? Are any versions of the big three (windows/mac/linux) known to suffer damage to OS integrity from a hard shutdown?

3. If there is any damage, is there any difference between the two methods, in terms of damage done?

Any and all answers appreciated.

 

A "Hard Stop" is fine when your computer is locked up with malware or other problems, however, the machines are not designed to continuously be turned off in this manner. This is why there are point and click methods of shutting down your computer. Doing a hard stop may prevent files from closing properly, resulting in corrupted data, may result in updates not completing their processes. IMO it's like yanking the spark plug wires off the engine of your car to turn it off . Would you do that every time ?
You may hard stop your computer for years and not have a problem, but the simple fact that these machines were not designed to be used in this manner is a good indication that you should probably NOT use them in this manner .

 

I think I need some clarification on this "not designed to" part. How ARE computers designed to shut down? What does a software shutdown do, that a power off does not, and why are those things needed ?

Good info, this is what I'm looking for. Any more specific insights would be great.

I'm afraid I have no knowledge of cars, so I don't honestly know. Though from what you suggest, that would involve opening the bonnet, and touching potentially hot/electrified metal, would could cause damage to yourself, never mind the car, so it may not be the best analogy.

The use of "may" implies a probability or dependance on circumstances. So if things don't go in your favour, what kind of problems would you see from this action?

Don't take this the wrong way, I'm not looking to be convinced of anything here. I avoid a hard power off when I can, but I'm looking to gain a deeper understanding of why we do this, and to expand my knowledge on a purely factual basis, not to have my opinion changed. So there's no need to tell me what is probably a bad idea. :-D

 

I'm no expert, but I'll tell you what I do know.

When shutting down using the OS, Windows for example, it closes all programs (and prompts you to save files that are being edited, etc.), locks the paging file, records information for the next startup (i.e. desktop icon order, etc.), and dismounts all storage volumes and media readers.

A hard shutdown doesn't allow any of this to take place. If files are open, only the previous state of the files before being opened will remain. If the hard drive is writing data, that will be interrupted, leaving room for corrupt data, or in some cases, a completely corrupted hard drive (same applies to thumb drives and removable read/write media like memory sticks). It also is one of the causes of the "NTLDR is missing, press CTRL ALT DEL to restart" message, because of this.

Also, a regular shutdown disconnects power in a certain order for the hardware, and undue stress is imposed when doing a hard shutdown on the hardware, since everything's designed to be turned off in a certain order. While everything APPEARS to shutdown at once, there's microsecond intervals. Note that I didn't say it necessarily damages the hardware, just puts extra stress on it, possibly leading to a shorter hardware life.

 

Lots of times, upon the next bootup, you get a message"Windows did not shut down normally last time" type of thing.
Then you have the option to Start Normally,or Last Known Good Configuration.

OR on the bad side, you get a no boot situation.

Sometimes you have no say in the matter. Will be working fine until somebody miles down the road takes out a power pole. Then just keep your fingers crossed.

 

Just confirming what's been said,usually nothing will be damaged but if the hard drive is writing the data can become corrupt,you can shutdown a thousand times with the power button and your comp will be fine then one unlucky one corrupts the harddrive.I've done this actually,with an older computer I just held the power button down every time I wanted to shut down and it was fine for months then it became corrupt and I had to reinstall windows.

The quality of your power supply plays a big part in how safe hard on and off's are,a good quality PSU has safety features in place that stop spikes and dips in power effecting hardware when the power supply is interrupted.

Turning the computer off by holding the power button in is the safest hard shut down and its designed to be shutdown this way without damage,turning off the mains as said depends upon the ability of your PSU to protect components,the worst hard shut down is pulling the AC or power cable directly from hardware,this can cause a spark that can damage sensitive components such as a the hard drive,connecting or disconnecting the motherboard power while the computer is on can fry the motherboard outright.