Multiple monitors detected that do not exist

[david gray]

Hi all,

I have a Dell M6800 laptop running Win10 and have two Dell U2412M monitors connected via DVI in a docking station. The graphics card is a NVIDIA Quadro K3199M according to the "Device Manager".

Problem I have is that according to Settings|Customize your display, I have monitors 1, 6 and 2 to 7. Detect seems to have found monitor 5 as well.

How can I reset this so that it shows monitors 1, 2 & 3?

Thanks in advance.

 

[Data]

Hello and welcome to forums.

This is a fix for Windows 7 but it also works on Windows 10.

See http://www.dell.com/support/article...cing-windows-7-to-rediscover-monitors?lang=EN

Note: I would advise you to make a backup of those registry keys before proceeding, despite them being recreated, you may decide to go back from some reason or whatever reason, its best to have a working backup.

 

[david gray]

Hi,
This did not work for me. I deleted all the keys for inside those two folders, restarted and I still have the same issue. I might try this fix again with just the laptop and no external monitors and then add them back in one at a time.

Thanks

 

[david gray]

Ok that did not work either. Because the laptop thinks it has three displays, when I reboot it there is no display as presumably it's trying to display the logon box on a monitor that is no longer connected.

In addition there appear to be no way of disconnecting 2|7 from settings.(See attached).

Not sure what else to do short of re-installing Windows.

 

[Data]

Well goes without saying that, you shouldn't plug any other monitors before deleting the keys and everything should be set to display on the main monitor.

It could help some reading this https://social.technet.microsoft.co.../reset-graphics-and-monitor-registry-settings

I dont know what else to contribute at this time, it should have worked.

 

[Data]

Can you show me a screenshot of your NVIDIA control panel that shows the port numbers where monitors are connected to another screenshot how the monitors are setup there under multimonitor setup?

 

[david gray]

Hi,
I set the laptop as the primary monitor, deleted all the keys and rebooted a couple of times so that I could be sure all reference to the other (external) monitors had gone. Booted the laptop without being in the dock and the laptop still thinks it has 1|2 and 5, the latter being disconnected. Trying to select monitor 1 only results in another "phantom" monitor being added.

The pics below are in chronological order. (7..8..9) and then there's a picture of the system topology.

Thanks

 

[Data]

Right, you should make sure that once everything is disconnected including dock and laptop is main monitor, then you delete the reg keys.

Its possible that despite the dock is disconnected that some other settings elsewhere being stored, which tbh I have no clew where as I dont own a Dell system anymore.

If there is any software installed for dock and userdata or programdata settings, make sure you remove those.

Then try again, if still ghost monitors being added and order is not as it should be, you may want to consider asking Dell for support. It could be an issue with dock itself some bug that causes this.

 

[david gray]

Hi,
I do have Display Fusion software installed , however I disabled that during this whole process. Might have to try all those steps again with this software uninstalled. Typically my three year onsite support from Dell ended about two weeks ago...

I also have a spare dock so will try with that.

I will post back here if/when I have resolved this.


Thanks for your help.

 

[Data]

Do these docks have firmware updates?

Are you actually trying to fix some actual issue?

 

[david gray]

Yes there is a problem(s) screen backgrounds overlap by 10cm or so onto the next monitor. And I had intended to use Display Fusion to snap certain Windows to a particular monitor, which does not work with these phantom monitors.

There's no firmware for the dock and the problem occurs without the laptop docked.

Thanks

 

[Data]

Sorry, I really have no further ideas about this, I tried with a Dell Laptop from a friends and no ghost monitors were created, he doesn't have a dock though and I used this guide http://www.dell.com/support/article...setup-multiple-monitors-in-windows-10?lang=EN
That clearly explains how to snap specific windows to a second monitors and not using display fusion.

Maybe someone else has further thoughts on this. Good luck.