Computer freezes when power cord is removed.

Hi all. I'm not sure which forum this problem would fit into, so I'm starting here.

I have had a problem for the last couple of months where the mouse cursor freezes immediately upon removal of the power cord. I have not been able to discover any way to recover aside from forcing a reboot. These reboots are often quite lengthy. Both the reboot and log in to Windows can spin for a long time, taking nearly 30 minutes or more. So while I've tried to be observant, testing is very difficult due to the amount of time necessary. Google searches have also been fruitless.

Some specs on my laptop:
Dell XPS L702x,
Dell Model No. P09E
Manufactured: 5/3/2012
Intel Core i7-2670QM CPU @ 2.20 GHz
8 GB RAM
64 bit operating system
Windows 10 Pro, 1903, 18362.720
External monitor, HP 25es

The problem often occurs when I disconnect the laptop (from the external monitor, power cord, etc.) to take it elsewhere. Initially I thought that the monitor connection was causing the problem, but it became apparent that it was really the power cord. Even a brief disconnection of the power adapter causes the mouse to freeze, but the monitor (HDMI) cable does not.

The battery works fine.

I believe if I put the computer to sleep first, the problem does not occur.

Also, at least sometimes, removing the external monitor first helps. I can't recall whether disconnecting the power with the lid open or shut is necessary.

When the freeze happens, the mouse ceases to function. If I recall correctly, the keyboard still works, but this might be the laptop keyboard only, not the external. I'm also not certain about the trackpad as I have the driver for this shut down.

This is a USB mouse. The battery is good. Using a wired USB mouse does not help.

OK, I know that is limited information. I can think of a couple dozen ways to test and try to narrow down the problem. But I don't have a couple of days to spend on rebooting this laptop as I work on it daily. So I'm interested in whether anyone else has encountered this sort of problem --- and not so interested in lists of things to try. Those lists can be more focused if we can identify where the problem might stem from.

Thanks,

Brad

- Have a look at Control Panel\All Control Panel Items\Power Options\Edit Plan Settings - Advanced - USB and disable USB selective Suspend (on battery mode)
- Open device manager. Is there any yellow alerts of missing drivers?
- Open a CMD window as administrator and type:
sfc /scannow

Jacee said:

You might also look into getting a new power adapter.

Don't think that the power adapter (charger) is related as the problem happens when you change from the state charger plugged in to battery mode.

Thanks for the suggestion. I agree the adapter is not suspect. I have two and the problem can occur with either.

Brad

Run the Dell customized diagnostics overnight with these checked boxes:
https://www.dell.com/support/home/en...l702x/diagnose

Code:

Performance
Bluescreen analyzer
Hard drive
Hard drive stress
Memory
Memory stress
Motherboard
Processor
Processor stress
System stress

Code:

Video capture
Video card
Video card stress

Take Screenshot in Windows 10
https://support.microsoft.com/en-gb/...re-screenshots
How to Upload and Post Screenshots and Files at Ten Forums



Find a camera or smartphone camera to take pictures and post images into the thread.

Post images of the tests performed and results into the thread.


Continue with the Dell customized tests (most are interactive)

Again make sure that you post images so that results do not disappear after an unexpected freeze and reboot.





1) Open administrative command prompt and type or copy and paste:
2) sfc /scannow
3) dism /online /cleanup-image /scanhealth
4) dism /online /cleanup-image /restorehealth
5) sfc /scannow
6) chkdsk /scan
7) wmic recoveros set autoreboot = false
8) wmic recoveros set DebugInfoType = 7
9) wmic recoveros get autoreboot
10) wmic recoveros get DebugInfoType
11) bcdedit /enum {badmemory}

12) When these have completed > right click on the top bar or title bar of the administrative command prompt box > left click on edit then select all > right click on the top bar again > left click on edit then copy > paste into the thread

Hi Brad, this sounds like it might be related to multiple power sources. Is the laptop charger, monitor and other related equipment plugged into the same power bar. If not, that's a very easy test to try.

W10 Tweaker said:

Hi Brad, this sounds like it might be related to multiple power sources. Is the laptop charger, monitor and other related equipment plugged into the same power bar. If not, that's a very easy test to try.

You should always use all power cables on same power bar to guarantee they have same ground.
Is your wall outlet grounded?
Is the phase and neutral on the correct pin?

zbook said:

Run the Dell customized diagnostics overnight with these checked boxes:

Thanks zbook. I'll give this a try, but it might be weekend until I have a chance.

- - - Updated - - -

Megahertz said:

You should always use all power cables on same power bar to guarantee they have same ground.
Is your wall outlet grounded?
Is the phase and neutral on the correct pin?

I doubt the house wiring is related, but I can check easily enough. The problem has occured both when in my office --- with external monitor, keyboard and power adapter connected --- as well as in another room --- with nothing but a power adapter and USB mouse connected.

blmiller99 said:

I doubt the house wiring is related, but I can check easily enough. The problem has occured both when in my office --- with external monitor, keyboard and power adapter connected...

The point that we're trying to make applies when using an external monitor as described in the original fault description. An external monitor should always be powered from the same power-bar as the PC in order to prevent a ground loop fault that could induce a harmful potential difference between the devices chasiss'.

This potential difference would likely create grief when devices are disconnected while powered or not, such as in the original fault description.

blmiller99 said:

--- as well as in another room --- with nothing but a power adapter and USB mouse connected.

This detail may sound insignificant, however; it is not. Are there any other nuances that could be used to describe your observations of the problem.