Mac mini external display issue

Anyone having issues with their external displays with their Mac mini? My 2018 running Catalina 10.15.7 is in need of an exorcism. I thought I would appeal to the group before I purchase a chicken to sacrifice.

I have two external monitors: The LG has an HDMI Cable directly to the Mac mini. The Dell has a micro display port to display port cable running from my Thunderbolt dock. Both monitors display data and images.

However, my screens go black at random moments. I can shake the display awake with the mouse but the frequency that this issue is recurring is a real pain. 5 times during this posting.

Diagnostics have been run and we are clear. The video purge (option/command/R/P contortion) has been done. We have restored the OS. The display sleep setting is turned off. I have new cables coming.

I would love to bring it to my local apple store however… all the Houston area stores are closed and the closest store open is in Austin (whole soapbox rant about this).

Thoughts, suggestions, incantations, spells, appreciated.


Maybe check your Energy Saver settings?

Do you have Mission Control Hot Corners setup by chance? I sometimes get too enthusiastic with the mouse pointer and hit the upper right corner of the display… boom…black screen

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Good one @MaxxHouseMaid!

Thanks - Energy saver is set for an hour. No hot corners to put the display to sleep. I am going through programs to see that I am up to date. Scratching my head on this one.

Did you try disconnecting one monitor and see what happens? May be able to troubleshoot by doing various combinations of inputs.

Right now we have both displays operating and have not had a black out this morning. The system OS restore may have finally completed after a series of restarts - during which I would have one or the other monitors working and some programs hanging. I think I am through with those gyrations and have not seen a beachball since the last restart.

One piece of hardware removed - an external WD Passport that was not working. Not sure that it was the culprit -but when dealing with the mysteries, I am not discounting anything.

I have a series of cables coming in: Mini DisplayPort to HDMI, Mini Display to Display Port, Thunderbolt to Display Port, Thunderbolt to HDMI. We will add them to see if there is any other issue.

Until then all I will keep the cables accessible…