Watch Dogs 2 black screen

The black screen can appear directly after the launch of the game or after a moment while playing.

You still hear the sound of the game, but there is no image anymore.

And you can’t switch between applications with the Alt+Maj keys combination.

The issue is due to your GPU that is too hot. It can’t work anymore.

See this article : How to check GPU temperature.

You have to cool down the GPU chipset. So shutdown your computer.

If the GPU is too hot, it is because the game requires too much from it. Your video card is not powerful enough.

You should think about to get a better card. Currently the best one by default is Nvidia GTX 1080. Nvidia GTX 1060 is a good alternative if you want a better quality/price ratio.