Flashing screen

[barbnor2]

Not sure what thread to put this on.
I have a Mac Mini M1. In the past week or two, my screen has started flashing 3 different times. I have to turn off the computer and restart. I have a DELL SE2719HR Display. I did a virus scan and did EtreCheck, but nothing showed up.

 

[Raz0rEdge]

What happens after the 3 flashes? Does the monitor go off or continue to operate?

 

[Jimmysb]

I started a thread about a similar problem on my Mac Mini M1 and a HDMI monitor, in the the screen shows "static", black and white dots flickering, it has been suggested that it could be the HDMI cable!

 

[barbnor2]

Well, I got a new mouse, changed HDMI cord and everything was fine for awhile. The flashing screen is back. When I said in the first post that it happened 3 times, I didn't mean that it flashed 3 times, I meant this had happened 3 times. Now it is happening again. It flashes really fast and the computer freezes. The cursor moves, but when I click on anything, nothing happens. I have to restart the computer.
I have a video of the flashing screen, but can't figure out how to upload.

 

[ferrarr]

Are you using an HDMI 2.0 (or better) cable?

 

[Jimmysb]

On my thread I have posted more details, but I have used two different cables with the same monitor, I then used a HDMI DVI-D converter and connected to a DVI-D input using a DVI-D cable on a different monitor, and it still happens from the HDMI output, which suggests the issue lies with the output, as both my monitions work fine in VGA.

Mac Mini - HDMI Monitor issue

I am running a Mac Mini (M1) with Ventura (13.1), which I have only recently bought. Initially I had just a HDMI monitor connected, and when the system went to sleep after a while without use when re-starting sometimes the monitor was just "static" black and white dot flickering. A google...

www.mac-forums.com

 

[ferrarr]

Again, if the adapter is not HDMI 2.0 to DVI-D, then that may also cause the issue.

 

[Jimmysb]

Again, if the adapter is not HDMI 2.0 to DVI-D, then that may also cause the issue.

Both of my cables, and my adapter are to the latest standard, or so their packaging says. However the Apple site does not mention standards for HDMI connection.

 

[Slydude]

If I'm understanding your symptoms correctly I've seen this before. I couldn't tell for sure from your post but are you using any adapters/connecters in addition to the cables?

I experienced this at one point for several weeks before tracing it down to the adapter I was using to connect the cable to the Thunderbolt port on my iMac. The failure on the adapter was intermittent and really inconsistent.

Edit: I suspect that the VGA connection is less prone to this issue because of the type of signal involved. IIRC VGA is an analog signal which will sometimes work if only part of the signal gets through. All digital signals tend to be an all or nothing thing. Someone correct me if I am wrong.

 

[Jimmysb]

Initially I connected my HP E202 HDMI in, via a HDMI cable from the Mac HDMI out, I have tried two different cables. I then connected my HPHP x20LED DVI-D in via a DVI-D cable connected to a DVI-D/HDMI adapter, to the Mac HDMI out.
The fault does not occur on start up, only sometimes after waking from sleep, but again it is only occasional, and cannot be repeated to order.

 

[Slydude]

I think that answers my question. If it were only occurring when the adapter is involved I would think that's the culprit. Since it's occurring both ways that's probably an adapter issue.

 

[Jimmysb]

I think that answers my question. If it were only occurring when the adapter is involved I would think that's the culprit. Since it's occurring both ways that's probably an adapter issue.

Sorry but that does not make sense, why would the adapter be the issue, when it is was not used on the first two occurrences of the issue. Surely the issue is with the HDMI output from the Mac.

 

[Slydude]

When I initially read your post, I wasn't sure whether the adapter had been used. I misread your post. Hence, the question.

 

[barbnor2]

What happens after the 3 flashes? Does the monitor go off or continue to operate?

Well, I got a new mouse, changed HDMI cord and everything was fine for awhile. The flashing screen is back. When I said in the first post that it happened 3 times, I didn't mean that it flashed 3 times, I meant this had happened 3 times. Now it is happening again. It flashes really fast and the computer freezes. The cursor moves, but when I click on anything, nothing happens. I have to restart the computer.
I have a video of the flashing screen, but can't figure out how to upload.

 

[barbnor2]

Are you using an HDMI 2.0 (or better) cable?

I can't tell if you mean me or the other guy? I don't know the answer. It was still in the wrapper. The rest of the thread is confusing because most of the answers are to the other poster, I think. Here is a copy of my info.

POSTED ON MACFORUMS 1-2-23

Not sure what thread to put this on.
I have a Mac Mini M1. In the past week or two, my screen has started flashing 3 different times. I have to turn off the computer and restart. I have a DELL SE2719HR Display. I did a virus scan and did EtreCheck, but nothing showed up.

REPLY – 1-2-23

What happens after the 3 flashes? Does the monitor go off or continue to operate? (Answered below)

Me AGAIN – 1-7-23
Well, I got a new mouse, changed HDMI cord and everything was fine for awhile. The flashing screen is back. When I said in the first post that it happened 3 times, I didn't mean that it flashed 3 times, I meant this has happened 3 times. Now it is happening again. It flashes really fast and the computer freezes. The cursor moves, but when I click on anything, nothing happens. I have to restart the computer.
I have a video of the flashing screen, but can't figure out how to upload it.

1-26-23
It hasn't happened since the last post. So I guess I have to wait until it happens again.