Why did Precision 7760 turn itself on?

A bit of a mystery. Tonight at around midnight I went to power on my precision 7760, and when I opened the lid it was already on. I am sure I turned it off on 11/10 when I last used it.

What is strange is that the uptime showed 16 hours and I slept in this morning until 10 so I wasn't even awake when it turned itself on.

I looked in the logs, and windows event logs shows it successfully shut down on the 10th at 4pm and then started this morning at 8:24 am (when the lid was closed, no one was here, and I was asleep).

I checked bios to see if wake on lan was enabled, but it was off in bios. (enabled in windows network adapter settings, but off in bios.)

In Dell Bios:
system management
wake on ac = off
wake on lan = disabled
auto on time = disabled

under system logs in dell bios:
power event log
11/18/2021 8:24:11 am Power On - Not Applicable

which reads the same as a normal power on when I hit the power on button, but I did not at 8:24 am this morning.

Any ideas on why a precision 7760 would just turn itself on from a powered off state when the lid was closed?

There is no dock, it is connected to ethernet, dell ac power adapter, and a logitech wireless mouse and that is all.

 

Could be power black out and resume without your knowledge. is the setting in the bios is auto on when power plug-in?

This happened to me on my 7720, black out for 10 seconds and resumed, and the laptop is turned on automatically.

 

It could be Dell Optimizer. Check all the settings.

 

Thanks very much to both of you for the replies. Will double check both things as it made me wonder if there was some kind of anomaly.

It's plugged into a brand new Eaton 1500S UPS (not connected via usb, only AC power connection from UPS) so it shouldn't detect a power blink if there were one. Will triple check that and bios setting.

I don't have the Dell Optimizer software component installed.

 

Weirdly it happened again today at 8:24 am. I had to search for this thread to see what time it happened before, and again this time it turned itself on with no one around at 8:24:22 am. (first entry this morning in windows event viewer)

I had checked and unplugging and replugging in the machine several times does not cause it to power on.

Event viewer shows when I shutdown at 3:53 am as "Shutdown type: power off"

Not sure what else to search for in the event viewer that could shed any light on why it's doing it, but I'm not seeing anything that would cause it to power on by itself. A little uneasy about it now.

 

Looking at the BIOS, System Log, the time is actually exactly the same as the November 18th event - 8:24:11 which can't be a coincidence. But I have no idea what would cause this to power on at 8:24:11 so it has me very uneasy.

12/18/2021 08:24:11 Power On - Not applicable

 

I think this has also happened to my 7730. Not when I have closed the lid though, but when I have turned the laptop off, left the lid open and when I came back in a couple of hours it was on the lock/log-in screen. I have not investigated it as I just thought it was me getting old and perhaps I was accidentally clicking restart instead of shutdown, or perhaps an update was happening that I did not know about. Will have to a look at the BIOS now.

 

Does a "normal" power on by pressing the button produce a different entry in the BIOS system log? (I haven't looked at it myself...)
...Maybe try resetting the BIOS to default settings (and then adjusting things back to how you like)?

 

Thanks very much for the reply. It actually happened the first time when I first got this laptop and was testing it -- I thought I must have hit restart instead of shut down too. When it happened in November, I felt uneasy because I wondered, am I getting old and hitting the wrong thing a second time? Then when it happened yesterday, I was 100% sure I didn't hit the wrong thing because I actually watched it shut down. Let me know if you find anything as it has me very curious what is going on.

Yes, just tested - a normal power on by pressing the power button produces the exact same entry in the bios system log: "Power On - Not applicable"

 

If the system is shut down with Start -> Power -> Shut Down can windows wake timers wake the system up somehow?

I would have thought that if a system was powered down with "Shut Down" there would be nothing about windows that was in any way running to run a wake timer. However, I wonder if there is some new magic windows 10 feature that I am not aware of that can somehow wake a computer from a power off (not sleeping or hibernating) state now ???

I was checking for anything and everything, and I found on this computer under power options, advanced, sleep, there was no "wake timers" option available. On my other computers it was set to "important wake timers only." I followed https://www.tenforums.com/tutorials...w-wake-timers-power-options-windows-10-a.html to add the registry value dword set to 2 to unhide this option, and then saw that on this computer it was "enabled." So I set it to "disabled" now. I thought this would only wake the computer from sleep or hibernate, but maybe there is something new that would somehow turn a computer on????

Under power options I already have "Turn on fast startup" unchecked.