Wake up/boot up to black screen

Question

Level 1

8 points

Wake up/boot up to black screen

My 2018 mac mini with Catalina 10.15.1 after waking, the screen is shifted off to the right with a 1/2" vertical dead space on the left side of the screen. The displayed information is also stretched sideways. If I power off the monitor then turn it back on it comes back to normal.

Other times, it doesn't come back on at all. Just a black screen. After many boot ups still just a black screen. I then "Zapped" the PRAM and the display came back on. I tried other displays and had the same problem. Not a happy camper!

Posted on Oct 31, 2019 9:29 PM

Reply

Answer 1

Top-ranking reply

wlrumble Author

Level 1

8 points

Nov 1, 2019 1:00 AM in response to hcsitas

I was using HDMI 2, I switched to HDMI 1 and set everything to the settings you suggested and the screen shift problem went away. I then set everything back to factory settings and it still worked fine. I then went back to the HDMI 2 port and the problem came back even with your suggested settings. I went back to port 1 and it works normally again. I put the computer to sleep several times and the screen came back normally. I guess I have a problem with port 2.

Here is what the screen looked like:

Reply

Answer 2

hcsitas

Level 6

13,964 points

Nov 1, 2019 12:06 AM in response to wlrumble

What port on the Samsung? Use HDMI 1 and then please check/set the settings to () from the Samsung OSD menu for:

Magic (standard)

Black Level (normal)

Eye Saver (off)

Game Mode (off)

Response Time (standard)

Picture Size (auto)

Freesync (off)

Eco Saving Plus (off)

Off timer (off)

PC/AV (PC)

Source detection (on)

Reply

Answer 3

wlrumble Author

Level 1

8 points

Oct 31, 2019 11:48 PM in response to hcsitas

HDMI cable.

Reply

Answer 4

wlrumble Author

Level 1

8 points

Oct 31, 2019 11:25 PM in response to hcsitas

The problem still exists. Zapping the PRAM got the monitor to start working again which got me back to the original problems with wake up.

My monitor is a Samsung model U28E590D. For now I am not letting the computer sleep or shut down. I am just turning off the monitor until hopefully Apple will have a software fix in the near future.

Reply

Answer 5

hcsitas

Level 6

13,964 points

Nov 1, 2019 1:07 AM in response to wlrumble

Happy to hear. Port 2 is 60 Hz. While in theory it should work, clearly it doesn’t, at least not perfectly. FWIW you can put the other settings except off timer back in sequence if you like, although I would let it be. Mainly gimmicks. Anyways, welcome to Catalina!

Reply