GV-N710D5SL-2GL (GTX 710) detects 2 displays when only one is connected

Hello,

OS: debian stretch (but I guess this doesn’t matter)

I’m having an issue with a GV-N710D5SL-2GL (rev 1.0) card.
I connect a monitor through a dvi cable. But when I go to display settings, it says there are 2 displays.
One is called “Monitor” and the other is the real name of the monitor that is connected.
But if I click on “identify screen” I see that I’m lookin at the “Monitor” on the physical monitor.
The nvidia-driver package is installed. (v390.138)
I have also tested the nvidia-driver package from stretch-backports (v418.152)
But I also installed a clean debian stretch and the issue remained. (meaning this is also the case with the nouveau driver as this is installed by default)
I installed debian buster to see if the issue also remained, but sadly it does.
I also tried to install ubuntu 20 on it, but this is a graphical installer and my guess is that the installer started on the not visible screen, so this was quickly aborted.

By default the screens are extended next to each other and so if a program start, they will be displayed out of my screen.
I have forced the displays trough xrandr to be mirrored.
xrandr says there is a VGA-0 and a DVI-D-0 connected. The VGA-0 only has 2 resolution options. Both very low (max 640x420).

I have tried 4 different GV-N710D5SL-2GL cards and 3 of them have this issue. They are all exactly the same graphics card. The 3 with the issue have a serial number that starts with SN173 and the other one starts with SN19…
I have inserted the 4 cards in multiple pc’s but the cards with SN173 keep giving me this issue!

When I swap cards (working vs not-working), the following command have the exact same output.
‘lshw’, ‘lspci’, ‘xdpyinfo’

Does anyone have any idea/guess what is going on?

Kind regards,
Matthias Roelandts