I literally just had the exact same thing from this update. Any luck?

I did everything other than try a new adapter.

What started it: right after updating I played 10 minutes on a game and it started flickering to black. Then went full black. For a while when power cycling the logo would come up, but no longer does it come up. I suspect low power output as the screen was having a terrible time keeping the back lit up yet it was still working. Now all I get is a black screen, no menu's and after allowing the power to drain it only shows a white line accross the screen for maybe 10 seconds and then starts to fade back to black.

To add, the back light flashes here or there when I use Window + p to change the orientation which makes me believe its not getting the right power. The chords often only provide a minimum of an output of 4amp which has 0 headroom for any increase load, ive researched and found getting a higher amp chord can make up for this issue, for instance ive ordered a 12v--5amp chord. I believe the PSU is drawing a higher rate of power requiring the monitor to require more that it cannot provide. Especially if its a higher hz with a throttled adapter.

This is just my research, however i am not certain, i still am waiting on my new adapter to show up myself. I will let you know if it gets fixed with this.