I have a Dell U2715H and occassionally, after short inactivity, I get a blackscreen for like two seconds. Afterwards, with no interaction, it just goes back to normal. This is probably not related to the VRM overheating issue since it's happening on Desktop as well.
 
What are the chances my 1080 might cause this? Or could the monitor be faulty? It's not the Displayport-Displayport cable since I tried another one.

Try a different dp output & make sure your dp cable is vesa certified.

Sajin
Try a different dp output & make sure your dp cable is vesa certified.

The only officially certified cable on Amazon Germany is DP 1.1a....does this matter versus a 1.2 cable at 1440p@60Hz? I need 2meters in length if this matters.

1.1a can do 1440p@60Hz no problem.

Try using a DVI connection if possible.
I used to get 2 second black screens until I changed from DP to DVI-D. I have ruled out the video card, so it is either an issue with my monitor, or a cheap DP cable

I just measured the pins on both my DP-DP cables and for both cables pin20 isn't connected! So no fuss about getting a cable listed on VESAs website....I also tried a random HDMI cable and the cable that came with the Dell U2715H, a MiniDP-DP cable, and both show the same behaviour.

The problem you describe, through the years ive had that on most of my amd Gpu's and mostly on windows 7. The screen would just blank out and come back in 1-2 seconds. As annoying as it was I never found the solution. Now i'm on windows 10 and havent had that for atleast 2-3 years.

velo-x
The problem you describe, through the years ive had that on most of my amd Gpu's and mostly on windows 7. The screen would just blank out and come back in 1-2 seconds. As annoying as it was I never found the solution. Now i'm on windows 10 and havent had that for atleast 2-3 years.

Strangely, I was not able to replicate the behaviour since like 24hours. Previously it was possible to just do nothing for a few minutes and it would have happened....
 
I noticed something else though:
When I shutdown the PC and WHILE the pc is shutting down I press the power off button on my monitor the following will happen: Few seconds after all the fans and LEDs have turned off the PC turns itself back on. This EXCLUSIVELY happens when I manually turn off the monitor during PC shutdown process. Doesn't matter if I use the original MiniDP-DP, DP-DP or HDMI-HDMI cable....