Question Does graphics card output signal on all ports?

Nov 27, 2021
Hi. I have GT1030 graphics card with HDMI & DVI-D output ports.
Currently I have hooked my monitor to HDMI out.
However does a card output its signal on all ports simultaneously or only the port that's connected?
e.g. does it receive something back from the display device like monitor to indicate that it's connected and send out signal only to that port or all ports always?
So if I switch from HDMI to DVI-D I hope it will still display on DVI-D and if I hook 2 monitors one on HDMI & another on DVI-D I hope it will take it to dual display mode?
Kindly clarify. This is a very basic doubt but could not find much info online, thanks in advance.


GPUs do not output to a port unless something is plugged in and they detect that something is plugged in by reading the Display ID chip that tells the GPU what resolutions and refresh rates are supported.

At boot, only the first monitor detected will get output for BIOS and Windows' initial load screen. If no monitor is connected, whatever port is the default will get output.

Once the OS and GPU drivers are loaded, the multi-monitor stuff kicks in and in most cases, this defaults to extending the desktop to extra monitors.
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