External monitor turning black intermittently
Solution 1:
This seems to be a connectivity issue. Try and wiggle the adapter, and all the connections while powered, and see if you can make the problem appear. Don't forget to test the connection at the display too.
Solution 2:
I believe it's most likely a bug in the generic Windows display driver. It's possible you can solve this with a driver from Dell for your display.
I've struggled with exactly that same behavior in one of my monitors, where it randomly goes dark for a couple seconds, then comes back on. The interval between could hours or it could seconds (almost constant flickering.)
In my case, it's two Dell 2405FPW panels side-by-side on my desktop and the problem only presented on my left monitor. Web searches at the time confirmed this a common problem, but seen only on the then-new Windows release I was running and could be traced to Dell having dropped support and not releasing a driver. The random behavior was because I was using the default driver. It drove me nuts for years (but I was too cheap to buy new panels that were supported.) The problem finally (fingers crossed) appears to have gone away a couple months ago with an Nvidia update for my graphics card.
In your case, I don't see others reporting the same behavior with your model and it looks like Dell still supports your monitor. But the behavior you're seeing is exactly what I saw from the default driver. This is why I suspect it may be as simple as downloading the proper driver from Dell.
Good luck. I hope this helps.
Solution 3:
I believe it is an HDMI issue as I am having the same problem with a new Vizio 50-inch LED TV. When using HDMI to watch cable tv or Blu-ray discs I get intermittent "no signal" displays where both video and audio disappear for a couple of seconds and then come back. Using component connections I don't have that problem. I don't like using component since the picture quality is not as good, but I can't find a better solution for the time being.
Solution 4:
There are many reasons why a monitor keeps turning off, resulting in a blank display. The best way to resolve this problem is through process of elimination; as such, I will go through the list of things you can do to help determine why the monitor keeps going black or turning off sporadically.
Simply put: both DVI and HDMI are digital signals; if the signal is too weak, the monitor won't sync to the computer, resulting in a blank screen. If the cable run is too long, or of the signal has been split (using a non-powered DVI or HDMI splitter), this can cause the monitor to go black because the signal isn't strong enough.
Based on my experience, some HDMI cables will simply stop syncing properly after a while, even though they worked fine previously, and even though the same cable works fine on another device. Sometimes, HDMI cables won't work properly if there has been a recent hardware configuration change. For example, you may have purchased a stereo receiver and ran the cable through the receiver instead of directly through the monitor. In this case, you can bypass the splitter or receiver and see if that makes any difference.
https://www.infopackets.com/news/9589/how-fix-monitor-keeps-going-black-turning
Solution 5:
I had this exact same problem with a Surface Pro 4, Monoprice monitor MP-28UHDSS. Seemed to start happening after the Windows 2018 May Update. I tried various suggestions, none worked for me until I went to Advanced Display Settings, Display Adapter Properties, and found that the screen refresh rate was set at 59Hz. No idea where that came from. I changed to 30Hz, and problem is definitely gone.