Question PC powers back on after shutting it down while it's using UPS power ?

[Asketa]

Recently I got a new PC and UPS. UPS is a bit weaker, but I don't need it to work for long - just to give me a couple of seconds to save my work in Word and turn my PC off manually. And it works fine. Power outage > UPS starts beeping > I save my Word document, close it > Power: Shut Down PC.

However, this is where I noticed a problem. When I turn off my PC, it automatically starts turning back on. First time I thought maybe I accidently hit "Restart" instead of "Shut Down". But it happened again.

I googled the problem and found a solution to change option in BIOS, "Restore on AC Power Loss". But, when I went to BIOS, I noticed that the option is indeed turned off.

P.S. My PC never starts powering up again when there is electricity, i.e. when I turn it off for the night, even though it is always connected to the UPS.

 

[Lutfij]

Make and model of your UPS? What are the specs to your build that's hooked to your UPS?

Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:

Can you relocate to another wall outlet?

 

[Ralston18]

Not sure that I understand the procedure being used.

When power is lost are you using the normal Windows Shut down or sign out option presented by right -clicking the Windows icon usually located in the lower left screen corner?

You do not need to or should not need to physically flip any switches.

Also take a look at the power plan setting.

You can do that via the Command Prompt (as Admin) and the "powercfg /l" command.

FYI (from my system):

C:\Windows\System32>powercfg /l

Existing Power Schemes (* Active)
-----------------------------------
Power Scheme GUID: 381b4222-f694-41f0-9685-ff5bb260df2e (Balanced)
Power Scheme GUID: 49ef8fc0-bb7f-488e-b6a0-f1fc77ec649b (Dell)
Power Scheme GUID: 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c (High performance) *
Power Scheme GUID: a1841308-3541-4fab-bc81-f71556f20b4a (Power saver)

Post accordingly.

 

[bill001g]

This is very strange how would the pc know what was connected to its power plug.

Although it might get a tiny glitch when the power goes from city to ups that is well before you attempt the shutdown.

All I can think of is the UPS does something strange when the pc goes from using power not using power when you turn it off.
You have already checked the setting about boot on power restore so if the UPS would drop the power for a second and then restore it the computer should ignore it.


Are you waiting for failures or does it do it if you unplug the UPS.

 

[Asketa]

Hi, thank you all for your replies!

UPS: Energenie EG-UPS-B850. It is 510W

CPU: 13th Gen Intel Core i7-13700K 3.40 GHz
CPU cooler: - not really sure how to look that up? Cooler Master MasterLiquid ML360R?
Motherboard: B760 AORUS ELITE AX (U3E1)
Ram: Kingston DDR5 32GB
SSD/HDD: SSD Kingston 2TB +2TB Seagate hard disk
GPU: NVIDIA GeForce RTX 4070 Ti 12GB
PSU: Seasonic g12 GM 850
Chassis: Cooler Master HAF 500
OS: Windows 10 Pro 64-bit
Monitor 1: AORUS FI27Q-P
Monitor 2: ASUS VA27EHE

Now, before you go saying that my UPS is weaker than it should be - I know. I mostly use it for writing my thesis in Word, and I used ampere clamp meter to check how much electricity I'm using. It was around 300-400W. I talked to the computer store seller and he recommended me this UPS.

But, that is irrelevant. UPS works fine. After power outage I have around 30+ seconds of electricity, which is more than enough to save my progress and turn off my PC and UPS.

Not sure that I understand the procedure being used.

I manually shut down my PC. Here is mine:
C:\Windows\system32>powercfg /l

Existing Power Schemes (* Active)
-----------------------------------
Power Scheme GUID: 381b4222-f694-41f0-9685-ff5bb260df2e (Balanced) *
Power Scheme GUID: 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c (High performance)
Power Scheme GUID: a1841308-3541-4fab-bc81-f71556f20b4a (Power saver)

This is very strange how would the pc know what was connected to its power plug.

I know, right? Perhaps he is becoming sentient?
I am just wondering, if the problem is with UPS - how is my UPS turning back on my PC?

Are you waiting for failures or does it do it if you unplug the UPS.

Waiting for failure. But I can try it now and report back...

 

[Asketa]

Are you waiting for failures or does it do it if you unplug the UPS.

I have just tested it. Unplugged the UPS from the wall outlet right after finishing my previous reply. It started beeping. I closed Chrome and turned off my PC. As soon as it was off (stopped producing any sound from the fans and monitor went black) it started turning back on again. Similar to restarting it.

However, when I turn it off when there is electricity and it's not using UPS' power, then it turns off normally and stays turned off.

It's like when it's using UPS's power, "Shut Down" becomes "Restart".

 

[Ralston18]

This UPS?

https://gembird.com/Repository/8707/EG-UPS-B850_manual---5ad32e4d-18ff-492a-97a6-3e56f1b12740.pdf

Are you using any power strips?

FYI:

https://forum-en.msi.com/index.php?...ac-power-loss-what-does-it-do-exactly.372552/

This BIOS?

https://download.gigabyte.com/FileL...bios_e.pdf?v=aceb9fb3f69cc73ea6b2fddd6a6f34ed

(Verify that I found the applicable manual.)

In any case take a look at the "AC Back" options on physically numbered Page 18.

From the manual:

AC BACK Determines the state of the system after the return of power from an AC power loss.
Memory The system returns to its last known awake state upon the return of the AC power.
Always On The system is turned on upon the return of the AC power.
Always Off The system stays off upon the return of the AC power.

= = = =

Also.

You posted that you had about 30 seconds to gracefully shutdown when power is lost. Is that because the UPS can only provide battery power for a very short time....?

Versus at least a few minutes.

 

[Asketa]

This UPS?

Yes, that's the one.

Are you using any power strips?

Actually yes, but the power strip is plugged into the UPS. The reason for this is that UPS only has 2 outlets (one for PC and other one for monitor). However, I do most of my work on my second monitor. I am afraid that if the power goes out and my other monitor shuts down, I won't be able to save progress, i.e. move all the open Windows to the primary monitor.

(Verify that I found the applicable manual.)

90% sure that it is. It looks like it, but I would need to restart my PC to be sure.

Always Off The system stays off upon the return of the AC power.

Yes. I thought that it is on, so I went to BIOS to turn it off. However, when I opened BIOS, it was on "Always Off".

As I sad in the original post:

I googled the problem and found a solution to change option in BIOS, "Restore on AC Power Loss". But, when I went to BIOS, I noticed that the option is indeed turned off.

Let me check it, and I'll get back to you.

 

[Asketa]

Here is my BIOS with options:

https://imgur.com/a/7sDWhqi

View: https://imgur.com/a/7sDWhqi


As you can, AC BACK is "Always Off" by default.

 

[Ralston18]

When you change change AC BACK are you sure to save and/or confirm the save before exiting?

And are there any dependencies (either way) with respect to that "Soft-Off by PWR-BTTN? What does configuration setting do?

= = = =

As long as you are saving your work it should not matter which monitor you are viewing the work on. And, if I am understanding correctly, there should be no need to drag any open windows between monitors when power fails. However, I do understand the issues if you are, for example, in the middle of some Copy Paste effort between screens.

Check the UPS manual regarding the use of a powerstrip. There could be some loop being created and causing a problem.

A loop being Device A connected to Device B connected to Device C connected to Device D connected to Device A again. Any such path, electrical, video, audio, network) can cause problems and confusion.

Are you using any UPS management software on you computer and getting UPS specs via a USB cable?

= = = =

Also; not within my comfort zone for such things (full disclosure) but is that VCCAS voltage correct or otherwise as it should be?

I noted that 0.818 voltage value which struck me as a bit unusual.

Will defer to those who work with such thing as to whether or not value is within the expected VCCSA voltage range and the correct voltage for your build.

No harm in asking....

 

[Asketa]

When you change change AC BACK are you sure to save and/or confirm the save before exiting?

I didn't change anything The default setting is "Always Off". I just opened and closed BIOS.

A loop being Device A connected to Device B connected to Device C connected to Device D connected to Device A again.

There is no "loop". PC is plugged into power strip, power strip into UPS, UPS into electrical socket in the wall.

Are you using any UPS management software on you computer and getting UPS specs via a USB cable?

Nah. I actually don't think there is any. It's a really robust and simple UPS.

I noted that 0.818 voltage value which struck me as a bit unusual.

I actually have no idea... I'm not very good with computers. I don't know what normal values are or how to check them

 

[Asketa]

And are there any dependencies (either way) with respect to that "Soft-Off by PWR-BTTN? What does configuration setting do?

Here is what it says when I click on it:

https://imgur.com/a/E6aNDOs

View: https://imgur.com/a/E6aNDOs

There is no "loop". PC is plugged into power strip, power strip into UPS, UPS into electrical socket in the wall.

Actually, the only loop that I can think of is that monitor is plugged into power strip and into my PC with both video cable and USB. It uses USB for RGB lights. But then again, speakers are also connected into the power strip and into the PC. Secondary monitor likewise.

But, I don't see how the loop explains why my PC is turning himself on automatically?

Check the UPS manual regarding the use of a powerstrip.

No mentions of a power strip in the manual.

 

[Ralston18]

Regarding surge protectors and power strips:

https://www.apc.com/us/en/faqs/FA156513/

https://www.apc.com/us/en/faqs/FA158852/

Above links are for informational purposes only: not recommendations or product endorsements.

(Note: your UPS is likely very similar to other brand UPSs with some differences with appearance, design, quality, etc..)

= = =

Consider that the PC is mis- interpreting a shutdown signal as a "restart". Or, in one way or another, there is a voltage present somewhere that is having the same effect.

Many of today's devices have what amounts to an "instant on" feature. The device is "off" but power is immediately available and usually indicated as being so via an LED.

End objective simply to provide for faster start ups. Trade-off being some energy wasted as some people view such matters.

With everything connected as you have described and with some uncertainty about the various BIOS power options it does not surprise me that the PC believes that it is to restart. Thus turning itself on automatically when you want the PC to stay off.

I have no immediate idea as to how the PC is determing that "it needs to restart".

= = = =

What to do:

My approach would be to reduce the devices to wall outlet, UPS, PC, and monitor. Nothing else.

You can simulate power outages by unplugging the UPS or turning off the circuit breaker serving the wall outlet.

Then work with the power related options within BIOS/Windows to ensure that the PC will power off when expected to do so and, likewise, restart when expected to do so.

Once that objective is achieved (and you know that BIOS/Windows is correctly configured) then methodically start adding back the other components. One at a time and continually test shutting down and restarting as you go.

Be aware of any subsequent loops being created. Keep the above links in mind. I recommend a simple sketch to keep track of devices, components, and all connections between them.

If the automatic restarts begin again somewhere along the way then you will at least know what device or connection caused the problem.

The "why" may take more work.

Or someone else may read this thread and post and spot some error of omission or commission on my part. No problem with that.