Display capture black screen on my ASUS with GE Force 940MX

[fragae]

Hi, I have just installed OBS, I can capture a window but not my full screen.
I have set the recommended config at https://obsproject.com/wiki/Laptop-Troubleshooting#configure-your-system-for-display-capture and it does not work. I have no more idea to make it work.
Can you help?
Many thanks :)