No bootscreen from usb-c ports on 2018 mini?

[omvs]

my colleague found that her new mini won’t give a bootscreen to her LG 4K UltraWide connected via usb-c, though once the os or recovery screen is up it’s fine, and a warm reboot does give a bootscreen. Connecting via hdmi also seems to work fine

I was planning on getting one myself, but I have a LG 5k UltraWide, and using hdmi restricts me to about 50hz. Has anyone seen this issue through thunderbolt?

 

[saulinpa]

I wonder if this is related to other Macs not working with DP 1.2 an 4k@60Hz ?

 

[omvs]

I wonder if this is related to other Macs not working with DP 1.2 an 4k@60Hz ?

Pretty sure we tried DP 1.1 also - I had past experiences with dp1.2 issues on my cMP and want4d to rule it out

And what’s weird is that once the OS video drivers kick in they seem to leave video in a state that’s fine for next reboot. Only cold starts are problems, which Ive never seen before. My guess is it’s a firmware bug, but she’s going to report to Apple and see what they say

Might also be only certain resolutions. 3840x1600 is an odd one. I’d be really curious if anyone has tried 5120x2160 on these machines, since that’s what i have

 

[AbSoluTc]

Something to test..

Connect an HDMI cable to the mini but don't connect it to anything. Leave the mini connected normally via USB-C and see what happens.

I have a mid 2012 connected to a Dell UW30 via DP and it would not show anything at boot via DP. Had to connect via HDMI. Finally just left the HDMI connected to the mini in case I needed it and since then (or maybe a firmware/os update?), cold boot/warm boot, have not had an issue. I get the screen. It's a bit wonky as the loading bar is messed up but I get the apple logo. More than I ever got before

 

[Gogaulin]

Pretty sure we tried DP 1.1 also - I had past experiences with dp1.2 issues on my cMP and want4d to rule it out

And what’s weird is that once the OS video drivers kick in they seem to leave video in a state that’s fine for next reboot. Only cold starts are problems, which Ive never seen before. My guess is it’s a firmware bug, but she’s going to report to Apple and see what they say

Might also be only certain resolutions. 3840x1600 is an odd one. I’d be really curious if anyone has tried 5120x2160 on these machines, since that’s what i have

I got one of the new LG 5k UltraWide today. I did have it happen to me one time when I did a cold start. I could see the boot up screen but could not see the login screen (weird). Reboots had no issue showing the login screen. I went back and shutdown everything and did another cold start and did not have the issue this time. I currently have the monitor connect by TB3 to the mac mini but I also have the DVI port connect to a windows 10 box. The Windows 10 box was turned off when I tested it.

 

[TheGreatDave]

I’ve got an LG 27 inch monitor that gives me no image on boot connected via DisplayPort to USB C. If I type my password in after the mac has booted it’ll switch on afterwards. Ended up switching to using HDMI and that’s fine.

 

[omvs]

FYI: Happens on my 34WK95U-W (5120x2160) if I use the displayport connector. Thunderbolt and hdmi are fine.

Apple actually gave my colleague a workaround involving nuking some files (not sure details - maybe where it stores the current res?) but didn't seem reliable so she switched back to HDMI.

Mine happened even on the very first boot out of the box, before i loaded any OS on it. So I reported it again - hopefully at some point they'll have an update.

 

[enri1357]

FYI: Happens on my 34WK95U-W (5120x2160) if I use the displayport connector. Thunderbolt and hdmi are fine.

Apple actually gave my colleague a workaround involving nuking some files (not sure details - maybe where it stores the current res?) but didn't seem reliable so she switched back to HDMI.

Mine happened even on the very first boot out of the box, before i loaded any OS on it. So I reported it again - hopefully at some point they'll have an update.

Do you get it resolved? I see the same issue with my 27uk650 as well

 

[Stephen.R]

I have had a reasonable amount of trouble with displays not being detected at all at boot, using a TB3 > Dual DisplayPort adapter from OWC. I assume most of you are using 'passive' USB-C to DP adapters?

 

[enri1357]

I have had a reasonable amount of trouble with displays not being detected at all at boot, using a TB3 > Dual DisplayPort adapter from OWC. I assume most of you are using 'passive' USB-C to DP adapters?

I am using this https://www.amazon.com/Plugable-USB-DisplayPort-Adapter-Resolutions/dp/B01EXKDRAC

You are using this one? https://eshop.macsales.com/item/OWC/TB3ADP2DP
and similar https://www.sonnettech.com/product/thunderbolt3-dual-displayport-adapter.html

It seems both of them are from 2016 (DP1.2)

I am interested to get it resolved if this can help. Do you have any more details why this work better?

Thanks.

 

[Stephen.R]

You are using this one?

Correct.

It seems both of them are from 2016 (DP1.2)

Seems so - I didn't have to set the displays to DP1.1 (they default to 1.2)

I am interested to get it resolved if this can help. Do you have any more details why this work better?

I'm not sure it does work any better - it has issues quite often, but it's possible it's a fault with my Mini, I'm taking it in for a tech to look at tomorrow or Friday.

I bought that adapter because I wanted to minimise port use - I originally intended to use DP 'daisy chaining' via MST, but the Dells only support this at 30hz, and from what I read (i never tried it once finding it forces 30hz) macos doesn't support MST for daisy chaining anyway (or not well at least?)

 

[enri1357]

Correct.


Seems so - I didn't have to set the displays to DP1.1 (they default to 1.2)


I'm not sure it does work any better - it has issues quite often, but it's possible it's a fault with my Mini, I'm taking it in for a tech to look at tomorrow or Friday.

I bought that adapter because I wanted to minimise port use - I originally intended to use DP 'daisy chaining' via MST, but the Dells only support this at 30hz, and from what I read (i never tried it once finding it forces 30hz) macos doesn't support MST for daisy chaining anyway (or not well at least?)

do they give you any direct feedback?

I am still waiting for their response

 

[Stephen.R]

do they give you any direct feedback?

Who is "they" in that sentence? I took my Mini into an Apple Service centre because it seemed to have the T2 issue. Not sure if you perhaps meant OWC regarding the TB3>DP adapter?

As it happens, the response from the service centre has not been great. Seems they ignored basically everything in the existing case notes and what I provided them, had a call today "it was just a software issue, you can pick it up now". Unless they meant firmware (i.e. T2 firmware) it sounds like a common ****** response for third-party service centres here.

 

[enri1357]

Who is "they" in that sentence? I took my Mini into an Apple Service centre because it seemed to have the T2 issue. Not sure if you perhaps meant OWC regarding the TB3>DP adapter?

As it happens, the response from the service centre has not been great. Seems they ignored basically everything in the existing case notes and what I provided them, had a call today "it was just a software issue, you can pick it up now". Unless they meant firmware (i.e. T2 firmware) it sounds like a common ****** response for third-party service centres here.

I see. this is sad. thanks for the update

Perhaps I should buy that thunderbolt to DP to get it solve

 

[gusping]

Happening to me to on my LG 4K monitor. Screen appears once i log in. Annoying, but I can live with it.