Monitor defect only on main rig?

[Dedzal]

Four days ago I finally switched to a 1080p 144hz display (coming from 900p 60hz) that I got as a birthday present from my friends and had absolutely no issues up until last night. Games were working flawlessly and GPU temps were in their usual range (30c idle GPU, 80c under heavy load), as they do and are even now.

I downloaded Stalker COP for old times sake and installed a mod with it but noticed there was some intense stuttering in the main menu (which turned out to be a game issue) even though Shadowplay showed me I literally had 1200 FPS. I could hear obvious coil whine coming from the GPU but it wasn't anything new to me as it happens in games like Overwatch as well. I still proceeded and started a new game but my PC froze for some reason during the loading screen and I had to restart.

After the restart I was searching to change some parameters in the game's text files but was suddenly greeted by a blank black screen (looking like the monitor was turned off even though the LED was blue indicating it was on). For a second I thought it was a game launching but I was sure that I didn't initiate any program/game. There was no cursor on my screen yet I could hear music playing in the background. Later I confirmed that even the keyboard was working by sending my friend messages after the screen had just turned black for another time. Windows Event Viewer showed no things out of the ordinary except the hard restarts I had to do to get my screen back (after experimenting even more I confirmed that a simple turn off - turn on of the monitor fixed the issue). Today I turned off the timer for sleep and automatic screen switch-off to see if the problem would still persist. I left my PC on during the day and when I came back home I returned to the same issue. The screen still dies at absolutely random times unrelated to GPU load. The GPU fans spin as usual and temperatures don't change at all after it happens. I've already tried reinstalling drivers, unfortunately to no avail.

 

After cleaning by GPU and checking for loose cables I enjoyed an hour of playing games, thinking the issue had finally gone away, however it appeared again while I was playing R6S, this time occuring much more frequently. I went back to desktop and wanted to do a system restore. However, half of my screen suddenly became darker while the other half looked like it constantly kept changing brightness. I switched back to my old monitor and had absolutely no issues gaming and browsing, meaning that the GPU is in fact not to blame. I connected the new monitor to my laptop where it also had absolutely no issues for hours.

For some reason both my PC and new monitor suddenly became incompatible with each other and I don't know how or why.
 

I'm still baffled after spending three whole days with new gear that changed my experience of gaming and then have it suddenly not work properly for some reason. I haven't found any valuable information on this topic on the internet so far. Any kind help would mean a lot to me and will be gladly appreciated <3

Specs: 
- Acer GN246HL
- i5 4670k (running at stock 3.4Ghz)
- GTX 770 2GB (stock settings) 
- 8 GB RAM 
- 700W PSU
- Asus B85M-E

[Alesek]

did you try to change the monitor inputs? but tbh, I'd just RMA it 

[Carbide X]

Im not gonna bother, reading this whole book you wrote hahah, but im just gonna advice this. delete drivers and reinstall them (ddu) or swap cables

[Dedzal]

1 hour ago, Alesek said:

did you try to change the monitor inputs? but tbh, I'd just RMA it 

Tried different cables still the same thing.

[Dedzal]

1 hour ago, Carbide X said:

Im not gonna bother, reading this whole book you wrote hahah, but im just gonna advice this. delete drivers and reinstall them (ddu) or swap cables

I already reinstalled drivers using DDU and switched between different cables but I still experience the same issue.