The real problem : the VG278Q doesn’t have any Deep Sleep option in the menu BUT I discover that when Adaptative Sync/FreeSync is OFF the problem disappeared too. The solution was to deactivate the Deep Sleep option. I read a lot on this and I also had this exact same issue with the PG279Q (A friend provide me the screen for a couple of days of testing). The result: all my windows previously placed on my second screen are moved to my main Monitor. When I activate the Screen Sleep in windows (for 1 minute or 10 minutes it doesn’t matters) the secondary screen recover faster than the VG278Q, then the VG278Q recover. To disable deep sleep, run the following command in Terminal: sudo pmset -a standby 0 This is a description of 'standby' (deep sleep) from the pmset man page: standby causes kernel power management to automatically hibernate a machine after it has slept for a specified time period. The problem: When Adaptative Sync/FreeSync is ON (activated) it seem that also the 'Deep Sleep' option is ON. Important note: I have a secondary screen (BenQ - HDMI) Just bought a brand new ASUS VG278Q to replace my BenQ XL2720Z (I had a black screen problem in specific situation due to firmware version, I decided to just to replace the screen with a similar one).
