(Apologies if this has been covered before, I searched) All NVidia multi display cards create the following debacle for their users:
* At boot time the BIOS will look for displays in a certain order. DVI has the highest priority. If you have a display on DVI and a display on HDMI, DVI will be the primary display and will show the manufacturer's logo and all boot messages. The exact order for a card with DP, DVI and HDMI outputs is DP-DVI-HDMI.
* When Windows starts, the OS and display drivers renumber the displays in a different, fixed order that can't be changed. This order varies depending on the ports provided on the card but it looks like HDMI0 - HDMI1 - DP - DVI for one variant of a GTX750 card I have seen with 2 HDMIs, 1 DVI and 1 DP.
* If not all the displays are connected when Windows starts and they get connected afterwards, Windows renumbers the displays in accordance with the above rules.
* The main problems are when people forget to turn on all the displays before the computer starts or there is a cable problem with one of the displays. When those displays are turned on or connected after Windows starts, the primary desktop display can end up going from your desktop monitor onto a projector or foldback screen unexpectedly. Very messy if you can't see the foldback screen to change the display settings on.
* A EW rep in our part of the world said he thought there were registry keys to control display numbering. I have looked into this and cannot find any support for this view. Unless NVIDIA chooses to change their drivers there is no solution for changing the numbering sequence.
* I have reluctantly concluded I must connect my desktop monitor to HDMI-0 and ignore the BIOS messages coming up on a different screen to make life simple.
* ATI cards seems to be able to display the BIOS messages on all the screens at startup.
Forums Migration
All NVidia multi display cards create the following debacle for their users:
* At boot time the BIOS will look for displays in a certain order. DVI has the highest priority. If you have a display on DVI and a display on HDMI, DVI will be the primary display and will show the manufacturer's logo and all boot messages. The exact order for a card with DP, DVI and HDMI outputs is DP-DVI-HDMI.
* When Windows starts, the OS and display drivers renumber the displays in a different, fixed order that can't be changed. This order varies depending on the ports provided on the card but it looks like HDMI0 - HDMI1 - DP - DVI for one variant of a GTX750 card I have seen with 2 HDMIs, 1 DVI and 1 DP.
* If not all the displays are connected when Windows starts and they get connected afterwards, Windows renumbers the displays in accordance with the above rules.
* The main problems are when people forget to turn on all the displays before the computer starts or there is a cable problem with one of the displays. When those displays are turned on or connected after Windows starts, the primary desktop display can end up going from your desktop monitor onto a projector or foldback screen unexpectedly. Very messy if you can't see the foldback screen to change the display settings on.
* A EW rep in our part of the world said he thought there were registry keys to control display numbering. I have looked into this and cannot find any support for this view. Unless NVIDIA chooses to change their drivers there is no solution for changing the numbering sequence.
* I have reluctantly concluded I must connect my desktop monitor to HDMI-0 and ignore the BIOS messages coming up on a different screen to make life simple.
* ATI cards seems to be able to display the BIOS messages on all the screens at startup.
### Edit: Fixed display order detection ###