So it's possible the ports on the monitor could have taken a hit but back to the new GPU. I don't see the make and model so I can't check if it supports your setup. HDMI LICENSING costs per port so many cards only enable one at a time so try the Mini-DP connection all on it's own to a DisplayPort on a monitor to test it out.
Also, drivers. Sometimes I have to use DDU (see google on what and how) to remove old drivers, then I can install the graphic cards drivers per the maker's suggestion. Usually that would be from the maker's site or from AMD or Nvidia directly.
Recently, both my Powersupply and my Graphicscards got fried for some reason, so I had to get both replaced. The new GPU is the exact same model as before (GTX970) but it has different Ports. Previously i connected my two screens via HDMI (Primary Monitor) and VGA (Secondary Monitor). The new GPU has one DVI port, which runs fine with a VGA adapter, and 3 Mini-DisplayPorts and 1 mini HDMI. I ordered a Mini-DP to DP cable, but I can't get any signal to my main Screen. My PC seems to recognize that the Monitor is connected, but on the screen it just says "No Signal" for a split second and then goes into stand-by mode. Connecting the screen via VGA seems to work fine, but thus i can't run both of my screens at the same time. I've spend hours looking for a solution but so far I've had no luck. Doesn't help that I am not super tech savy. Does anyone have an Idea what might be wrong? Are the Ports on the GPU just screwed?
Main Monitor Model is: ViewSonic VX2757
I'd be gratefull for any help!

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