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Problem with Dual Monitors and Catalina on HP 800 G1 SFF

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I'm wanting to post on the thread referenced inline below, but I don't have enough rights to do so.  Maybe someone so post a cross reference/link for me, otherwise I guess I could try tagging @Donw35 directly:


Firstly, the work of @Donw35 just looks awesome.  I am able to get full compatibility between Catalina and my HP 800 G1 SFF if I use a single display (via the top onboard DisplayPort connector).  As soon as I add a second monitor (again just using the onboard iGPU, i.e. the Intel HD 4600 but via the 2nd, lower Display port connector), I am getting a reproducible kernel panic every boot, just at the point where macOS normally tries/switches from the text mode boot to the Apple logo.  (I'm in verbose mode - so this is quite far through the boot sequence, nearly to the point where the logon/window manager usually appears.)


I'm getting this behaviour both with HP_800_G1_OC063.zip and earlier EFI build HP_800_G1_OC_58.zip.


I'm also on the latest BIOS for the board, which is v02.78


I would quite like my dual monitor setup - so for the time being I have gone back to High Sierra.  (I know that my hardware is fine because I've been on 10.13 on the HP 800 G1 for some time and have had no issues on the dual monitor setup.)


Is there someone who can please help with this issue - would quite like to move to a newer version of macOS, but I guess there's no huge rush.


Thanks in Advance,



Edited by prynhart
Add thread I'm referencing

Check the patches to the Azul framebuffer or the graphics property injections you were possibly applying in High Sierra. Your OC config shows nothing outside the mandatory injection of the usual Azul desktop platform-id and the (possibly unnecessary) injection of HD4600 desktop id.


You are therefore running on the default/vanilla pipe and connector values when these may require to be modified.

Thanks @Hervé - if I were to upload a ZIP of my current (working) EFI for High Sierra do you think you might be able to have a look at it ?  I actually just used this prebuilt Clover environment with very minor tweaks  via Clover Configurator (just to set the processor type to Haswell and the Graphics to HD4600): https://hackintosher.com/guides/high-sierra-install-full-guide/.








For the file (tar with gzip)





For the file (tar with gzip)





Exactly, hence why I said to post only the config file or the patched ACPI tables, NOT to post the entire Clover EFI !  :whistle::whistle:


Anyway, outside the expected selection of the required Azul platform-id, there's no specific properties injection for your HD4600 graphics in your High Sierra setup, so... Add the ACPI patches of your High Sierra config to your OpenCore config, especially the renaming from GFX0 to IGPU.


Good luck.

Ah right - sorry @Hervé.  The new guy gets it wrong.


Anyway - so we've got no real reason why there should be a spontaneous reboot in the case of the macOS 15 setup ?  If so - I might need the help of @Donw35.


It's reproducible every time - unplugging the second display and everything is perfect under Catalina.  Plug it back in and game over.

Ah @Hervé - Looks like you edited your post after I replied.  There wasn't this sentence when I replied:


"Add the ACPI patches of your High Sierra config to your OpenCore config, especially the renaming from GFX0 to IGPU."


Now there is.  Okay - something for me to follow up on.





The software used for this forum is a bit ..... unusual.  If I "Submit a Reply" to my own post, it seems to duplicate the entire previous post that I made.  Weird - I guess maybe I'm supposed to Edit the last existing post (rather than Reply to my own post ?)


Edit: Except that time!  Must be client side I guess, but I'm just using Safari (as shipped with macOS 10.13)

Edited by prynhart

I've never had any Haswell desktop, only a Haswell laptop. Mobile HD4600 always required to patch the framebuffer and change the pipe of the connector for the HDMI port from 0x09 to 0x12; failing what, system would freeze/crash/KP when HDMI was plugged in.



Maybe you need to do the same though it's weird you wouldn't have had the same issue in High Sierra.


Oh well, 'beats me!

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