My previous setup was a laptop and a second monitor.
Then now i have a pc and have a new monitor with an rx 5500 xt that has 1 hdmi and 3 DP ports.
My new monitor is on hdmi and 1month after i bought a dp to vga adapter so i can use my old monitor that i was using with the laptop.
The problem is when i boot up the old monitor is doing fine but goes "No signal" after that. But the windows can still detect it. I can still move my mouse pointer on the 2nd monitor and can al see it with a screen shot.
So i was thinking the adapter i bought is faulty. But then my new monitor also has a vga port. So I tried the adapter with a vga cable on my new monitor and it works fine!
So i dont know which is the problem anymore. I also tried another old monitor which also works fine with my laptop, same things happened.
I have a rx 5500 xt, i dont know if it affect the problems. I was thinking maybe the problem was d-sub input monitor but i dont know exactly what it is.