Question Display Port no signal after boot

Jan 8, 2021
Since yesterday I get "no signal" via display port after windows has booted. I get the post screen, the windows logo shows up with the spinning dots, and after that the screen goes black with the no signal error. I get signal when I connect through HDMI though, no problems there, but then the refresh rate is lower.

This is a brand new build and it worked perfectly the other day. The monitor is about 4 years old.

My monitor is a Asus vg248qe (1080p 144hz), GPU is Zotac 3070 RTX.

So far I tried to reïnstall graphics drivers, power cycling the monitor multiple times and booting in safe mode (still no signal).

I also tried a 165hz 1440p monitor this week, but I did not like it and sent it back to the store. I used that monitor in a dual setup with my Asus to compare them. Maybe that screwed something up in Windows? I don't know... I Googled all over and cannot find anything that solves my problem :( I guess maybe the display port input is broken? Though it works during bootup because it shows the mobo post screen and windows logo.

I'm at wits and and really hope some hero here can help me!