[Solved] Latitude 7390: HDMI issues

[FoUStep]

I have a Latitude 7390, it worked fine with Mojave (and a EDID Override) for the AOC-display (1080p Q40G027N with internal speakers) at my work. I've tried several of this monitors and with Catalina (10.15.3 overwrite of Mojave, Hervé's guide with DSDT removed) there seems to be an issue with the HDMI connectivity. The screen sometimes flashes when connecting and it turns itself off / no signal.

 

After plugin it out and in for a few times the screen or turning the screen off and on it seems to work. It might be a configuration file which does not initiate properly. A HDMI beamer (w/ sound)  that I tried in another did not have these issues (and with the EDID Override on Mojave I did not have these issues either, the screen worked fine for more than a year). I removed the EDID Override profile because it only changed the colors under Mojave from really purple to normal.

 

If the screen connects (and it works) then it continues to work as long as I do not disconnect the HDMI or lock my screen. Does anyone have any suggestions since the guide from Hervé's stated that it should work out of the box.

 

Information when the external display is working:

Intel UHD Graphics 620:

  Chipset Model: Intel UHD Graphics 620
  Type: GPU
  Bus: Built-In
  Slot: Built-in
  VRAM (Dynamic, Max): 1536 MB
  Vendor: Intel
  Device ID: 0x5916
  Revision ID: 0x0007
  Metal: Supported, feature set macOS GPUFamily2 v1
  Displays:
Display:
  Resolution: 1920x1080 (1080p FHD - Full High Definition)
  UI Looks like: 1920 x 1080 @ 60 Hz
  Framebuffer Depth: 30-Bit Colour (ARGB2101010)
  Main Display: Yes
  Mirror: Off
  Online: Yes
  Automatically Adjust Brightness: No
  Connection Type: Internal
2775:
  Resolution: 1920x1080 (1080p FHD - Full High Definition)
  UI Looks like: 1920 x 1080 @ 60 Hz
  Framebuffer Depth: 30-Bit Colour (ARGB2101010)
  Display Serial Number: KNHG3JA000330
  Mirror: Off
  Online: Yes
  Rotation: Supported
  Automatically Adjust Brightness: No

 

[FoUStep]

Updated to the newest (7 days ago) Lilu, WhateverGreen and AppleALC. To no avail unfortunately.

[Hervé]

https://osxlatitude.com/forums/topic/11410-dell-latitude-7490-with-i7-8650u-intel-uhd-620-and-1920x1080-lcd-mojavecatalina/?do=findComment&comment=94753

 

[FoUStep]

I've replaced the config.plist in my EFI from the 7490_Mojave_Clover_Pack_#8.zip file of your Mojave and this seems to work. Isn't this implemented in your Clover Configuration Pack #2 for Catalina? Thank you for your solution. Am I missing anything else? I tried a few times and it seems to work fine now.