Mac mini doesn't display an image on startup when using USB-C to DisplayPort

[weaztek]

telling people to just wait for the next version of OS which might fix it isn't a great answer. Especially as they've just released a major update and its not done anything.

I don't think the "bulletin" posted in the other thread is genuine.

 

[ascender]

I don't think the "bulletin" posted in the other thread is genuine.

No, I just saw that thread. Neither analyst mentioned it and both were keen to make sure I was on the latest build of Catalina.

 

[ascender]

Another long call yesterday where we tried a few things with no joy. Very helpful and knowledgeable guy but nothing has worked so its off to the Apple Store I go this weekend.

 

[ascender]

Am back from the Apple Store with a replacement Mac Mini, place your bets now as to whether it works or not?

I’m going to say “no”, but you never know....

 

[ascender]

Well, I don't want to tempt fate, but the replacement Mac Mini has been working for a day, connected to the 4K monitor over USB-C without any issues waking from sleep or power off.

 

[gravelld]

Just registered to add my voice to this. I have a Mac Mini 2018 with Catalina on it. Monitor is a HP ZR24w. Mini DP -> DP worked fine in an older 2011 Mac Mini.

USB-C -> DP won't work... most of the time.

HDMI -> DVI works every time.

I can't use HDMI -> DVI long term though because I have another computer that uses the DVI input on the monitor.

I have no idea what combination of plugging in/out of the HDMI makes the USB-C -> DP wake up, but it definitely has worked once or twice.

 

[Fishrrman]

gravelid wrote:
"USB-C -> DP won't work... most of the time.
HDMI -> DVI works every time."

Fishrrman's credo:
"When one method doesn't work, but another method does, use the method THAT WORKS, and don't worry about the rest..."

 

[gravelld]

"Fishrrman's credo" ought to include reading the entire post.

 

[Fishrrman]

"Fishrrman's credo" ought to include reading the entire post.

I -did- read the entire post.
You can either go with the method that works, or struggle along with one that doesn't.
Your choice.

 

[gravelld]

"I can't use HDMI -> DVI long term though because I have another computer that uses the DVI input on the monitor."

 

[H2SO4]

This is a bit off topic but same general subject.

Mac Mini 2018
Newish Dell P2415Q 4k monitor
HDMI to HDMI high-speed cable.

Everything worked fine under Mojave. I installed Catalina and the monitor received no signal from the computer. I went back to Mojave and still no signal (just a black screen).

I tried everything including a different high speed hdmi cable but nothing worked. Finally I switched the monitor into HDMI 1.4 only mode and everything works 100 percent of the time ( but at 1080p 30 hz).

I've got a DP to usb-c cable arriving today and hopefully that will allow me to go back to 4K at 60 hz.

EDIT: The DP to usb-c cable got here and everything works great. System information shows the following just as I want; no more blank screen on startup; and sleep works also.

Resolution: 3840 x 2160 (2160p 4K UHD - Ultra High Definition)

UI Looks like: 1920 x 1080 @ 60 Hz

Hi, can you tell me exactly which one you bought pls?

 

[mofsoft]

Just another voice added to the list.

I can confirm that the i7 Mac mini 2018 running Catalina (10.15.1) with two Samsung U28E510 4K displays...

• with FileVault turned ON and displays connected via USB-C to DisplayPort
  • ==> presents a blank screen when booting up
    • note: when you get the black screen, just tap the CAPS LOCK key a few times to indicate the system is ready to receive input, then blindly type your password and press enter... it will then continue booting into your desktop
• with FileVault turned OFF and displays are connected via USB-C to DisplayPort
  • ==> correctly presents the login screen when booting up
• with FileVault turned ON and display is connected via HDMI to HDMI (and all other display cables disconnected)
  • ==> correctly presents the login screen when booting up

On a side note, in a support article titled About encrypted storage on your new Mac, Apple claims "Though the SSD in computers that have the Apple T2 Security Chip is encrypted, you should turn on FileVault so that your Mac requires a password to decrypt your data". I guess the Mac mini 2018 does encryption by default but can also be decrypted without a password if you don't turn on FileVault. It seems a bit vague to me...if you turn off FileVault in order to avoid the blank screen at login, your ssd is still encrypted... but if someone gains access to that ssd, can they decrypt it?

 

[olahaye74]

Same problem for me with my new Mac mini 2018 (Macmini8,1) bought on Black Friday 2019 connected to a MSI MAG321CURV (4K Curved display).
Filevault is turned on.
Ran Mojav, then upgraded to Catalina 10.15.1 then upgraded to 10.15.2
Same behavior for 3 OS:
Connected to HDMI: I must blindly type my password, then after a few sync/no-sync signal, I get the image.
Connected to USB-C (this screen has an USB-c (DisplayPort) input. No image. (do I need to turn off Mac to change connection?)

I didn't test to disable Filevault yet as it says it may takes time.
I have 300GB on disk.... How much time could it take? (I don't want a fief so see my personal documents such a photos and more. How can a crypt software alter a Intel Graphic 630 output? wired it is)...

 

[Krevnik]

I didn't test to disable Filevault yet as it says it may takes time.
I have 300GB on disk.... How much time could it take? (I don't want a fief so see my personal documents such a photos and more. How can a crypt software alter a Intel Graphic 630 output? wired it is)...

It’s more that FileVault adds a step to the boot process. One in firmware, not the OS itself. It needs the FileVault password to be able to decrypt and boot the OS. So there’s something about how the firmware itself starts up that would cause the problem.

 

[Henrique Ferreira]

I'm experiencing exaclty same issue. I need to type my password blind in order to use the computer. My display is iiyama xub3493wqsu-b1.

Tried HDMI-HDMI, HDMI-USBC, DP-USB-C

No joy with them. Wtf Apple!

 

[H2SO4]

I'm experiencing exaclty same issue. I need to type my password blind in order to use the computer. My display is iiyama xub3493wqsu-b1.

Tried HDMI-HDMI, HDMI-USBC, DP-USB-C

No joy with them. Wtf Apple!

I’ll add LG 38UC99 to that.

 

[watakoola]

I'm experiencing exaclty same issue. I need to type my password blind in order to use the computer. My display is iiyama xub3493wqsu-b1.

Tried HDMI-HDMI, HDMI-USBC, DP-USB-C

No joy with them. Wtf Apple!

Can you try HDMI to DisplayPort?

 

[H2SO4]

Can you try HDMI to DisplayPort?

I've had the same on HDMI, that's why I tried USBC.

 

[mofsoft]

Happy to report that this issued seems resolved with macOS 10.15.4.

Mac mini 2018
2 USB-C-to-DisplayPort 4K Samsung monitors
FireVault turned on

Startups/Reboots display the login screen

Note: This was tested on a fresh install of 10.15.4 and not an upgrade from 10.15.x

 

[H2SO4]

Happy to report that this issued seems resolved with macOS 10.15.4.

Mac mini 2018
2 USB-C-to-DisplayPort 4K Samsung monitors
FireVault turned on

Startups/Reboots display the login screen

Note: This was tested on a fresh install of 10.15.4 and not an upgrade from 10.15.x

Really annoying that it took this long as Mojave is just fine for me.

 

[1MrBee]

This same issue is on the NUC computers by intel. I had 7 NUC‘a before I gave up. The issue is the security chip. I have not enjoyed computers since this issue began. If I cannot get this 2020 Mac to work properly it’s the end of computers for me! I’m done with constant issues!