Ive had this problem since June, havent been able to find a solution :(
I had it too... Just go to bios and click on reset all to deafult ... Go to google ad your type of BIOS and watch info how to reset it :) ... It works everytime I had problem with it ...
HI GUYS, I'VE JUST FOUND THE SOLUTION TO THE PROBLEM AND HOPE THAT IT HELPS YOU
So i have a 120hz monitor and was using the dvi dual link cable, but the dvi port died so i switch to hdmi, but i wanted the 120hz and the hdmi was operating at 60hz, so i created a custom resolution in the nvidia panel with a 1080p output at 110hz because thats all the hdmi could do, everything was fine until i updated the nvidia drivers, the witcher 3 stoped working, it would not load, just a black screen for a couple of seconds and then nothing.
THE SOLUTION: just go back to native 60hz or delete the custom resolution and create it again.
i think i'll have to do this every time i update the drivers, i hope this helps you guys ...