I noticed that the screen turns black for a moment when a certain amount of electrostatic current is generated, I have a fabric chair that if I wear some type of garment generates an ESD (electrostatic discharge) while I get up, I feel it because if I have the speakers on I hear the rustle, at that moment the monitor turns black for 1 second, it happens sometimes when I turn off the speakers that have internal power and is therefore located at 10 / 15cm from the monitor, this has never happened with the previous monitor.
For G-Sync problem, I have find this solution (and it work):
"I have a 1080ti and needed to use CRU to change the freesync range from 48-164 to 50-164 to prevent it from blanking sometimes."
But I stop to use cause brightness flickering, that no one manufacturer has ever deigned to resolve. So I noticed this problem.