Windows 10: 2nd Display becomes primary when main monitor is switched off

Hi,

I have the following problem for a few weeks now:

I have a "main" monitor attached to DVI and a beamer attached to HDMI of my GTX-960 graphics card. The monitor is set to primary display.

For watching movies, I usually switch off the monitor, leaving only the beamer turned on. For a few weeks now, the beamer automatically becomes primary display when I turn off the monitor. It did not do this before. This behavior is very annoying, because it brings a black screen for a few seconds whenever I switch on/off the monitor, which I sometimes do while a movie is running. In addition KODI sometimes crashes in this moment and PowerDVD stops playing the movie.

The only thing I have changed at that time was that I manually changed the beamer to primary for watching a 3D blu-ray, but I changed it back when the movie was finished.

Does somebody have an idea about what causes this behavior and - more importantly - how I can stop this, i.e., keep the monitor beeing the primary display even when it is turned off?

Thanks for all ideas!


:)

 

Dual monitors--I cannot change primary monitor

Something changed recently and my #2 monitor switched to #1 and primary monitor. It is grayed out when I try to switch monitors. I can drag them around--but I can not switch number 2 monitor to number one. I noticed this a week or so ago.

I have shut computer off--restarted with just my main monitor on--as soon as I pug the second monitor in--it becomes primary monitor.

help

 

Windows 10 shows the 2nd monitor has 1920x1080 but actually is less than 50% around 1080x840

The resolution of the 2nd monitor, a Vizio VF551XVT 55-inch 1920x1080 HDTV connected through HDMI cable, shows 1920x1080 (Recommended) on the Windows 10’s Display Screen Resolution setting utility but the true resolution of the 2nd monitor is less than
50%; around 1080x840. All applications on the 2nd monitor displayed their header & boarder frames twice wider on screen, which waste/occupy lots of the 2nd monitor’s display area. Please help solving this critical lower than the set/expected 2nd monitor screen
resolution problem. Thanks.

The 1st/primary monitor in this case is a mobile PC Display (1920x1080), Lenovo Z710 Intel i7 4710MQ notebook with NVIDIA 840M graphic processor. Previously running under the Windows 8.1 OS with the same configuration, the 2nd monitor resolution also was
displayed incorrectly but just initially right after the Windows 8.1 reboot, i.e. 2nd monitor shows 1920x1080 resolution but actually the 2nd monitor is about the same as Windows 10, display resolution is much/50% fewer than 1920x1080. However, the resolution
of the 2nd monitor (HDTV) under Windows 8.1 can be corrected (worked around) by switching the main display from 1st to 2nd monitor, then switching main display back from 2nd to 1st, but in Windows 10 OS seems no work around.

Also
1) Please advise if Windows 10 can fix the application displays re-position issue when the develop support team fix the Windows 10 incorrect display 2nd monitor resolution problem above. The re-position issue is, when a TV, DVR, Xbox, and PC, shared 2nd
monitor is disconnected to watching TV, etc., Windows OS currently moves all the application display positions, both active and minimized displays, from 2nd monitor to 1st/main screen/monitor, but ideally would be just moving/re-aligning the active displays
to the main/1st monitor and maintain/leave those minimized display positions intact, so when 2nd monitor reconnects back (done watching TV, DVR, Xbox), user doesn’t need to re-align all the displays back for 2nd monitor again, user can just click/activate
those minimized displays to show/run displays at their previous positions if Windows OS knows to keep them intact.

2) Please advise how does Windows allow user to select/choose which monitor to display the media at full screen. currently Windows OS seems displaying almost all apps’ full screen mode at 1st/main monitor. It seems not easy/possible for users to show slideshows
at the 2nd monitor or/and switch between monitors. One way to make monitor selection easy could be displaying the full screen at the same monitor that the app is displaying prior to switching the app to the full screen mode - in my two cents.

Thanks in advance for the helps.

 

Hi @ai5g ,
Welcome to tenforums! *Smile
Are you using the WinKey+P to modify monitor projection or, are you simply turning the monitor off with the physical power button?

 

The latter, I turn it off with the power button.

 

Hmm, I was concerned that I am just too stupid... But now I feel better since even you guys here seem not to know the answer ;-)

However, any ideas how I could approach the problem?

 

I habe just noticed that the monitor disappears from the display settings once it is turned off. In contrast, the beamer remains in the settings even if it is turned off. Is there a way to stop the monitor from disappearing from the settings?

 

Another observation:
First oft all, thanks Edwin for the win+p idea, I didn't know this shortcut. If I use this to set "secondary only", this switches the PC monitor off, which is strange because the PC monitor is the main display (which should make the beamer secondary in my opinion).

 

"Second Screen only" means that only the secondary monitor is active (on), that will turn off the primary display. The Monitor set as the main display will turn off.
"PC Screen Only" will reverse that, Primary will be On, Secondary off.
"Extend" is both on.
"Duplicate" Is both on but they mirror each other.

 

Yes, but it behaves differently, as I said. However, I found a workaround. My graphics adaptor has two DVI-ports. Plugging the monitor into the other port prevents this problem.