Is My Laptop Ever Truly Powered Down?

[Melbourne Guy]

TL;DR Summary

I know my desktop PC has a mechanical power switch, but do laptops?

My Dell Latitude laptop has been a little fussy recently when booting with the USB-C / Thunderbolt dock plugged in, causing a few "hold the power button down for thirty seconds" events to restart it. Which led to the errant thought, is it ever actually fully powered down? Or is the power button a soft switch?

And as a note, even though it would probably have been quicker to google the answer than write this post, I figured the PF community is more fun to engage with on superfluous questions like this

 

[pbuk]

Most laptop power switches are soft switches. In most cases the "hold the power button down for thirty seconds" or similar action discharges a hard-wired capacitor or similar circuit which causes temporary disconnection of the power supply to all digital circuits.

 

[Melbourne Guy]

Thanks, @pbuk, that's along the lines of what I thought, good to have it confirmed

 

[FactChecker]

Any safe shutdown using the power button should be a soft shutdown, whether it's a laptop or a tower. That prevents disks from becoming corrupted and any hardware from being damaged by a surprise power shut-off. That being said, all computers require the ability to completely shut down safely for repairs. (Desktop PCs also have a small battery that keeps the clock running and does not turn off.)
There are some things that can stop a computer from completely shutting down. That might be what you are witnessing.

 

[Melbourne Guy]

There are some things that can stop a computer from completely shutting down.

Thanks @FactChecker, I think it is completely shutting down - as much as Win10 does - it's just that I wondered what that actually means. I have read that Windows 10 (which my laptop is running) has a 'fast startup' that is usually enabled and which puts the laptop into a semi-hibernation mode when you 'shut it down', and I expect that is occurring because I've not disabled it.

 

[phinds]

I have read that Windows 10 (which my laptop is running) has a 'fast startup' that is usually enabled and which puts the laptop into a semi-hibernation mode when you 'shut it down', and I expect that is occurring because I've not disabled it.

That sounds like the "sleep" option

 

[pbuk]

Thanks @FactChecker, I think it is completely shutting down - as much as Win10 does - it's just that I wondered what that actually means. I have read that Windows 10 (which my laptop is running) has a 'fast startup' that is usually enabled and which puts the laptop into a semi-hibernation mode when you 'shut it down', and I expect that is occurring because I've not disabled it.

That sounds like the "sleep" option

No, fast boot is a feature of the UEFI BIOS which operates at a lower level than sleep or hibernation which both operate at the OS level.

• Sleep - OS shuts down power-consuming components such as display, audio and suspends userspace processes; maintains system components to respond to interrupts from (user configurable) components such as USB devices (keyboard, mouse) and Ethernet.
• Hibernate - OS suspends userspace and system processes, writes memory content to disk and tells the power supply to remove the power from the rest of the system.
• Shut down (without fast boot) - OS closes userspace and system processes and tells the power supply to remove the power from the rest of the system.
• Shut down (UEFI BIOS, fast boot enabled) - OS closes userspace and system processes, writes certain information to a special disk partition (which can be read by the BIOS before the OS is reloaded on startup), and tells the power supply to remove the power from the rest of the system.

 

[FactChecker]

My new tower computer does not seem to have a hibernate mode. I miss that. It was a way to shut down, knowing that power outage was not a threat, without having to save the current work. Was it too complicated to implement thoroughly?

 

[pbuk]

It's a feature of the operating system. I believe in Windows 10/11 it is turned off by default when the system does not have a battery, but I'm pretty sure it can be enabled in system power settings.

Edit: or maybe not (I have 80GB of RAM on this system so maybe it thinks it is not worth it!)

Edit2: Control Panel -> Hardware and Sound -> Power Options -> System Settings

Edit3: Although it is titled System Settings once you have got there, the menu entry is actually Control Panel -> Hardware and Sound -> Power Options -> Change what the power buttons do

 

[FactChecker]

It's a feature of the operating system. I believe in Windows 10/11 it is turned off by default when the system does not have a battery, but I'm pretty sure it can be enabled in system power settings.

Edit: or maybe not (I have 80GB of RAM on this system so maybe it thinks it is not worth it!)

Edit: Control Panel -> Hardware and Sound -> Power Options -> System Settings

I went there and the hibernate option is not selectable for the power menu, but it was an option for the "moon-shaped" function button. I will try it.
It worked! It did a complete power shut-down but was able to come back up with all the programs as they were before the hibernate.
Thanks!

 

[phinds]

Hibernate is normally disabled by Windows if there is a solid state boot drive because hibernate uses a ton of writes and SSDs don't like that.

 

[Melbourne Guy]

My new tower computer does not seem to have a hibernate mode. I miss that. It was a way to shut down, knowing that power outage was not a threat, without having to save the current work. Was it too complicated to implement thoroughly?

@FactChecker is correct, you need to enable hibernate mode as an Admin in the 'Power and sleep settings'. It used to be enabled by default, but some years ago it was disabled.

Hibernate is normally disabled by Windows if there is a solid state boot drive because hibernate uses a ton of writes and SSDs don't like that.

I understood that Fast Start was intended to supersede hibernate, @phinds, rather than it being SSD triggered. And while SSDs do 'wear out' from write cycles, manufacturers estimates of terabytes written (TBW) is high enough that hibernate won't especially effect it, you're more likely to expire the 5-years (typical) warranty. SSD controllers usually apply a wear-leveling routine to evenly distribute data over all cells, and a TBW value of 70 would require users to write 190GB daily for a year to reach it. The 1TB Samsung in my laptop has a 150 TBW and I expect the SSD will outlast Dell's driver update period, at which point I'll pony up for a new machine.

(Edited to change my laptop SSD from 1GB to 1TB. Must of had a brain fade back to the early days of hard drives. One gigabyte, indeed )

 

[jedishrfu]

This is why folks suggest removing the battery from a laptop to really insure that it is off. Of course, fruity laptops from an unnamed vendor among others do not have that option.

 

[Borg]

Definitely turn off the Fast Startup setting!

Fast Startup does leave the computer in a powered mode and it is enabled by default on Windows 10. I turn it off on all of my computers. I even had a conversation with a sysadmin at my wife's company about turning it off on her computer because of problems that she was having - it requires admin privileges to turn it off.

From what I've seen and understand, it keeps your RAM active so that it "restarts quicker" even though the time difference is negligible (especially if you have an SSD). The problem is that, if there is a problem that would be taken care of by a normal shutdown, your RAM hangs on to the problem - you are forced to do a reboot to actually clear the RAM. Most people don't realize this and think that turning it off and back on accomplishes the same thing.

Since the RAM is kept active, all kinds of things happen that normally would get cleared. Did Excel crash last time? No problem. We'll bring back that same broken configuration! Did you get a soft system update that didn't require a reboot? We'll ignore that and keep using the old version that may not be compatible with the updated files! Lots of fun and games to figure out on your journey to software hell. Turn it off.

More from Microsoft on Fast Startup - https://docs.microsoft.com/en-us/tr...loyment/updates-not-install-with-fast-startup

The Fast Startup feature in Windows 10 allows your computer start up faster after a shutdown. When you shut down your computer, Fast Startup will put your computer into a hibernation state instead of a full shutdown. Fast Startup is enabled by default if your computer is capable of hibernation.

Installation of some Windows updates can be completed only when starting your computer after a full shutdown. Since Fast Startup uses hibernation instead of a full shutdown, installation of those updates will not be completed before a full shutdown. In order to make sure pending updates are completed, you have to choose Restart from the Power menu.

Here's malwaretips thread on problems that people have had with it:
https://malwaretips.com/threads/turning-off-fast-startup-makes-windows-and-other-softwares-more-stable-and-can-solve-many-problems.106091/

 

[Melbourne Guy]

From what I've seen and understand, it keeps your RAM active so that it "restarts quicker" even though the time difference is negligible (especially if you have an SSD). The problem is that, if there is a problem that would be taken care of by a normal shutdown, your RAM hangs on to the problem - you are forced to do a reboot to actually clear the RAM. Most people don't realize this and think that turning it off and back on accomplishes the same thing.

That's likely what's been occurring with my USB-C / Thunderbolt dock, @Borg. I tend to plug and unplug so I can use the laptop around the house, so Win10 is possibly being confused by what state it is in when it fast starts. I'll disable it and see if it helps!

 

[Borg]

Let us know how it goes.

 

[Melbourne Guy]

Let us know how it goes.

@Borg, I've fixed my problem, but fast startup did not seem to be implicated, because I disabled it, and there was no change to the bootup behaviour. But I did disable Thunderbolt on the USB-C port and that seems to have sorted it out. Possibly, Thunderbolt on the laptop and Thunderbolt on my docking station were not quite in sync, but whatever the cause, the docking station is happier just using USB-C.

I'm not sure there is anything useful for others in that, but I guess it reinforces that PCs are complicated beasts with many things to trigger user frustration