Jtdylktuy

I've added a secondary monitor to my PC. And I've configured it to be in portrait mode and everything is fine when I'm in windows. But when I restart, the boot screen shows in the portrait monitor. I've searched all over the BIOS but found nothing. Switching the cables and ports also did nothing. So how can I fix this problem and set the landscape monitor as my primary display?

I'm gonna go ahead and post this debug plan as a separate answer, so we can discuss the details in the comments.

I want to figure out ...

• if the problem is GPU DVI output specific. So, I want to make sure I understand correctly what you mean by "Switching the cables and ports also did nothing".


• if the "portrait mode" is relevant in the issue. So you should try setting this to landscape, and try again with monitor 1 on output 1, and then monitor 1 on output 2.
  
  
  
  
  • If the portrait mode is relevant in the issue, you should upgrade your BIOS driver and GPU firmware (just to make sure you're at the latest version). Then test again. If the problem persists, you should open a support ticket with your GPU or Motherboard vendor (not sure which of the two would be most relevant), then it sounds like a firmware issue.
  
  
  • If the portrait mode is not relevant in the issue (would be weird). It must be screen specific. Yet, to be completely sure it's not the cables, try a full swap of both (so screen 1 - GPU 1 stays screen 1 GPU 1, just using the other cable).
  
  
  
  

For good measure, I'd like to get the details on the connectors and cables straight (for reference):

• Your GPU has one DVI-D (dual link) and one DVI-I (dual link) connector, right?


• Your cables are both DVI-D (dual link) cables, as you said?


• What are the connector types on your monitors?

@HosseinMaktoobian what your trying to accomplish is usually not supported by most motherboards since they don't have any advanced graphics. When you change it in Windows it's only changed on the OS level

To Easily set Windows to start on a designated monitor every time you start windows/log in:

• open Scheduled tasks: C:WindowsSystem32taskschd.msc
  


• on left column, select Task Scheduler Library to be able to view tasks


• on right column, select Create Basic Task
  


• enter name for task (with no spaces, example: Monitor_Startup), click next


• select When I log on for When do you want the task to start?, click next


• select Start a program for What action do you want the task to perform?, click next


• enter c:windowssystem32displayswitch.exe for Program/script
  (when entering all data on my post, only enter the data between the ' 's, do NOT enter ' 'single quotes)


• enter /external OR /internal for Add arguments (optional):
  (sometimes you have to guess which argument to use, because they are not necessarily named according to which monitor you think is internal/external)


• click Finish
  


• reboot and see if you have the right argument (/external or /internal),


• if windows started on the correct monitor, you are finished, windows will always start on the same monitor.

If windows still starts on the wrong monitor, modify the task to switch the argument:
- open Scheduled tasks: C:WindowsSystem32taskschd.msc
- on left column, select Task Scheduler Library to be able to view tasks
- in the middle column, locate the task you created (scroll if necessary), right click it, click properties
- click the Actions Tab, click edit
- switch the argument (/external from/to /internal)` , and click ok twice
- reboot. Windows will always switch the monitor when you log on.

If you choose to stop this scheduled task, delete it:
- open Scheduled tasks: C:WindowsSystem32taskschd.msc
- on left column, select Task Scheduler Library to be able to view tasks
- in the middle column, locate the task you created (scroll if necessary), right click it, click delete, click yes.

I hope this resolves your problem.

other than setting the other monitor as a slave.

I would recommend switching accounts. Logging in as new user/guest.

Windows key + P

selecting the main display. Which should show as either 1 or 2.

then the option to make this my main display. Restart the computer. force log off the other user.

If you are on windows 10 go to settings -> display -> click on your monitor you want as your primary monitor, then scroll down until you see "Use as your primary display" or something like that.