[FAILURE] Monterey on HP Compaq Elite 8300 All-In-One

[HarFanG]

Alright. But can you answer what method and what software did you use to extract the EDID?

Wow. I did so many things and didn't took notes about every each of them XD
Maybe I used IOReg ?
The only thing I'm sure, it's that I used an hex editor to check the content of the saved file in the end.

Oooops...I just noticed I'm using my born language. If you want, I can switch to an english Big Sur

 

[EliteMacx86]

Using a clone copy, I kept searching...
Knowing the LG can do 4K and the HQP only 1080p, I changed the screen resolution to 1080p : in case of HQP receives >1080p and was out of range...

Then, I noticed something strange : in System Configuration, HQP seems to be set exactly as the LG...
Something came to my mind : what if HQP & LG are cloned displays ?

After that, I tried to play with DP, and the joined pic is my best try.
And on the last pic, shouldn't the HQP need to have "Internal" checked ?

What do you think, these can help ?

Well, what I'm concerned about is how you extracted the EDID. As the configuration is less cluttered, it's the EDID for sure. So, I'm asking you again to explain me how you extracted the EDID. Once i get that information, we can dive deep and sort the issue.

 

[EliteMacx86]

Wow. I did so many things and didn't took notes about every each of them XD
Maybe I used IOReg ?
The only thing I'm sure, it's that I used an hex editor to check the content of the saved file in the end.

Oooops...I just noticed I'm using my born language. If you want, I can switch to an english Big Sur

Nah, nah. You're not understanding it probably. What did you use to extract/fetch the EDID? Did you use Windows? Mac? Ubuntu? What OS? What software? I do know that EDID is in HEX, so I'm not asking that.

And yeah, I'm not sure if you used IOReg to get the EDID. That's the reason I'm asking you how you extracted the EDID.

 

[HarFanG]

Hmmm...I believe I extracted it from W10 but don't remember how.

FOUND IT : https://www.nirsoft.net/utils/monitor_info_view.html

The best move we can do right now, isn't "to know how I did" but you, explaining me how to extract it the right way.

 

[EliteMacx86]

The best move we can do right now, isn't "to know how I did" but you, explaining me how to extract it the right way.

Well, seems like you did not read carefully. Read post #70. What you mentioned after was, you're not familiar with Ubuntu. You just need a bootable USB and can boot from the live to extract the EDID.

But it seems like the EDID extracted is in the correct length. Still further investigation is needed. It could be the Display brightness. So, grab SSDT-PNLF from the official OpenCore package and inject it. Boot the system without the external monitor connected and then attach a copy of System Report+IOReg.

 

[HarFanG]

As I don't have any problem with french & english, for your convenience, I switched system language to english.

And there are the 2 files asked, still nothing on the HQP...

 

[EliteMacx86]

As I don't have any problem with french & english, for your convenience, I switched system language to english.

Appreciate that!

And there are the 2 files asked, still nothing on the HQP...

Do you see a brightness slider in the System Preferences>Display? Use VNC or your external monitor to confirm that.

Also, if you have Windows, disconnect the external monitor and dump the EDID.bin using MonInfo on Windows. Once dumped, attach it to double check. Having one SKL HP AIO and one Notebook. Both use LG panels and the EDID is quite similar. But your looks way more different.

 

[HarFanG]

Appreciate that!

You're welcome !


Well, I used Puppy Linux to extract again the EDID.
And guess what ? The file is exactly the same as the one did on Windows.

No, there is no brightness slider anywhere

 

[EliteMacx86]

Well, I used Puppy Linux to extract again the EDID.
And guess what ? The file is exactly the same as the one did on Windows.

Now, that's a good confirmation. So, we can stick to that EDID.

No, there is no brightness slider anywhere

Really?

Something is wrong then!

 

[HarFanG]

Yeah, and I dunno why
The only slider available is "colour".