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Mac Mini 2018 HDMI failes after OS upgrade / patch
- Thread starter tstimper
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Indeed:
A Long, LONG time...
In a galaxy far, far away....
That we Intel users with Catalina will never get to see or visit...
Oh oh.... screen went black for a few seconds this morning. I hope it’s a one off glitch. This is a bit like tiptoeing through a minefield - will my next step make everything go black?
ha yes, this is a software issue. A lot of us had various display issues with the new Mini when Catalina was rolled out (thank it was Catalina, discussion has been going to quite some times . It ALL revolved the OS. it's been documented that it was introduced with Cataline ( think) and has to do with the AMD drivers I think. Nonetheless, I relayed this on this very very long thread multiple times but I feel l ike the OP is really married to a hardware issue. I was having display issues for awhile, in particular when I use an EGPU. but the last couple updates fixed it.
I think. it was introduced with the upgraded firmware with Catalina. I was running into eh intermittent black screen for months, once I completely wiped out the OS (I reset it so it's started from the very first OS the machine arrived on (Mojave) and the issue was resolved. I had the Mac mini 2018 for months working perfectly. the Firmware introduction of Catalina is what cause the issue. they did realse an update that corrected the issue roughly 6 months ago.
Oh no!!!! Updated to 11.2.3 and the black screen issue is totally back again. What on earth are Apple doing? They have lost the plot!
Happened to me on the latest patch, I use mine with three monitors, 1 HDMI and 2x displayport. The displayport monitors come up but not the hdmi monitor. The only reason I use macos instead of windows is imessage and password manager integration, if they ever brought those to Windows I would never use macos in a million years, it‘s inferior to Windows in every way except for Apple ecosystem integration.
The “fix” is let it come up on the DP monitors, force shutdown by holding the power button. Disconnect the DP monitors and leave only HDMI plugged in, reboot, once the HDMI monitor displays the login screen plug in the DP monitors and it’s back to normal.
The “fix” is let it come up on the DP monitors, force shutdown by holding the power button. Disconnect the DP monitors and leave only HDMI plugged in, reboot, once the HDMI monitor displays the login screen plug in the DP monitors and it’s back to normal.
I have been using an HDMI to HDMI cable between my Mac Mini and my new LG OLED65CX with no problems. Yesterday, my TV says "No signal!" I tried multiple HDMI to HDMI cables. Nothing. I plugged in my Acer monitor with various HDMI to HDMI cables. Nothing.
MY SOLUTION: I happened to have a cable with Thunderbolt on one end and HDMI on the other. Plugged it in and everything is good. And the weird thing is that after the picture came back up on my TV...my original HDMI to HDMI cable now works again! Weird! It's like the Thunderbolt to HDMI cable somehow "reset" my Mac Mini so the HDMI port now works again.
MY SOLUTION: I happened to have a cable with Thunderbolt on one end and HDMI on the other. Plugged it in and everything is good. And the weird thing is that after the picture came back up on my TV...my original HDMI to HDMI cable now works again! Weird! It's like the Thunderbolt to HDMI cable somehow "reset" my Mac Mini so the HDMI port now works again.
I've been experiencing dead-HDMI issues on 2018 Mac Mini / Mojave 10.14.6, latest security update (as of March 22, 2021). Attached HDMI devices were simply not recognized at all. Thanks to this thread, I believe I've traced the problem to the Apple security update which I recently installed.
POTENTIAL WORKAROUND:
In at least two instances so far, I was able to get my Mac Mini to recognize a connected HDMI TV, by turning on the TV at the same time as plugging it in. Suddenly it was recognized, and began working normally.
My hunch is that the issue relates to HDMI hanshakes / negotiation at time of connecting.
My display config is:
1) TB3>Displayport cable>LG 3440x1440 ultrawide
2) TB3>DVI adapter > older Dell 1920x1080 via DVI
3) HDMI rear port > Samsung 55" TV
POTENTIAL WORKAROUND:
In at least two instances so far, I was able to get my Mac Mini to recognize a connected HDMI TV, by turning on the TV at the same time as plugging it in. Suddenly it was recognized, and began working normally.
My hunch is that the issue relates to HDMI hanshakes / negotiation at time of connecting.
My display config is:
1) TB3>Displayport cable>LG 3440x1440 ultrawide
2) TB3>DVI adapter > older Dell 1920x1080 via DVI
3) HDMI rear port > Samsung 55" TV
doesnt work for my Mac Mini 2018 down to 2 displays w/Big Sur (every version tried) = 1 TB3 + 1 USB-C to HDMI on second TB3 bus controller--so if this works with previous OS caution advised on updating to Big Sur. I never had this problem btw through Catalina
New to this forum. I have the 2018 mini, minimum configuration (i3, 8gb 128gb) Just updated to Big Sur 11.3.1. I just start experiencing this hdmi black screen problem. It hs gone from intermittent to frequent in 2 days. Monitor is an older Dell Ultrasharp with DVIand Displayport inputs. I use a DVI-HDMI adapter on the monitor - no cable. HDMI cable is an older Apple branded cable. I tried another hdmi cable, while on the phone to Apple support. Video was fine or about 5 minutes, then, after telling support the problem was fixed, it cameback even worse. I had tried a promotional CLDAY USBC to 2xHDMI splitter a few months back. It didn’t deliver extended mode 3 suport but allows me to connect my monitor via a thunderbolt port. Works flawlessly. I will be back to Apple looking for a Geniuss Bar appointment.
Join the club. Totally fed up with Apple regarding this issue. Good luck with your appointment.
This morning I double check both of my monitor. A Dell running hdmi through a hdmi to dvi adapter. No signal. An LG running straight hdmi. No signal. Nothing particularly special about either. Using an actual Apple HDMI cable. Both monitors performed properly when connected TB to HDMI using a CLDAY TB to HDMI cable I got from Amazon. I dropped the unit and Apple cable off at 11:30 AM. They called me at 3:30 to say the unit had been running with my cable for 3 hours with no issue. I picked it up and got it reconnected to the Dell monitor, running without incident for a little over 4 hours. I have shut everything down for the night. Will see how it goes in the morning. Go figure…
After resting over night, the HDMI remains asleep. One thing sticks in my mind though, is the 13.3.1 update was a PITA to install. The download was good, the install at the "10 minutes remaining" point took about 5 hours.
I'm in the club Janeilfen, pretty sad.
I'm in the club Janeilfen, pretty sad.
I've been dealing with this with Mojave, Catalna, Big Sur - I think its fixed, then its not - no rhyme or reason. I finally just stopped sleeping my two monitors and just use a screen saver of a blank screen, which does keep the backlight on unfortunately. Most days I remember to turn off my displays at the end of the day.
Edited version number….sorry
So with macOS 11.4 I have HDMI on an LG27MP35, HDMI to HDMI. my Dell U2412Mb did not accept HDMI to DVI but does accept TB/USBC to HDMI to DVI. Neither SYSTEM PREFERENCES > Displays nor System Report > Graphis/Displays show the Dell U2412M model number. I did the PRAM reset and it is better. The Dell was getting the LG profile which was green and messy. Now the Dell Model and profile are recognized. When I add the LG using TB to HDMI cable, the Display Arrangement can only be changed in the LG(TB) display. Otherwise the mouse cursor is in the LG and the keyboard is connected to the Dell (HDMI). But after about 15 minutes of messing around, the HDMI screen did some cycling on and off. It has been steady for the 5 hours but still goes off occasionally when 2 monitors are connected, very steady with just one monitor When I power off the TB connected LG, the full screen does not return to the HDMI connected Dell until I disconnect the cable from the LG. It seems as though the LG display is always the boss when connected. Does that make any sense?
So with macOS 11.4 I have HDMI on an LG27MP35, HDMI to HDMI. my Dell U2412Mb did not accept HDMI to DVI but does accept TB/USBC to HDMI to DVI. Neither SYSTEM PREFERENCES > Displays nor System Report > Graphis/Displays show the Dell U2412M model number. I did the PRAM reset and it is better. The Dell was getting the LG profile which was green and messy. Now the Dell Model and profile are recognized. When I add the LG using TB to HDMI cable, the Display Arrangement can only be changed in the LG(TB) display. Otherwise the mouse cursor is in the LG and the keyboard is connected to the Dell (HDMI). But after about 15 minutes of messing around, the HDMI screen did some cycling on and off. It has been steady for the 5 hours but still goes off occasionally when 2 monitors are connected, very steady with just one monitor When I power off the TB connected LG, the full screen does not return to the HDMI connected Dell until I disconnect the cable from the LG. It seems as though the LG display is always the boss when connected. Does that make any sense?
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