Computer with dual monitor setup showing black screen on game launch

Just purchased two Dell U2715H 27" monitors the other day and a Dell XPS8900 tower.

intel Core i7
16GB Ram
NVidia GTX 960


I am having an issue where when I launch two steam games I run into a crash. The games i'm trying to run are "Pure Pool" and "Pool Nation FX". Both games sometimes run without any issues, but occasionally when the game has ended the screen which I was gaming on will turn completely black, not even backlit, just black.

Also when I launch the games sometimes the monitor in which the game is running will be completely black, not even backlit, but i'll still be able to hear the sound.

What is really odd is that when I close the program such as the pool game, the black screen will still remain. (please note I can still use task manager on my other monitor).

Also, sometimes when I finish playing either game I won't get any black screen, but when I come to restart my computer one of my monitors will be black, not even backlit as before.

I can run DOTA 2 without any issues at all. This PC and monitors are both new purchased this week.

One thing I also notice is that when running in Window mode it tends to perform better, but yesterday as I was playing Pure Pool, the screen just went randomly black even when in windowed mode.

Noticed yesterday that the screen went black even when doing a non gaming activity so now I know it's nothing to do with the games themselves. I tried changing the cable from MiniDP to HDMI to see if the issue might be with the cable itself.