Latitude 7480: Grey screen on USB key boot

[cinoyter]

Hi all,

I am having a grey screen with moving mouse cursor when I boot from a USB installer (Ventura). So it seems to "boot up" but instead of showing any UI, it shows a grey screen.

I have tried to make my own configuration (attached) and have also tried the one in this thread and I have the same results. I am telling myself it is most likely because of the high-resolution screen on this computer but I'm not sure what to do.

I'm not sure where to go from here because I can't dump the boot messages nor are they logged anywhere but I'm happy to produce any logs that are available.

 

System specs: i7-7600U, 16GB RAM, 512GB M.2, Intel HD 620, 2560x1440 screen.

 

Thanks!

 

config.plist.zip

[Hervé]

I don't fully understand why you inject some graphics properties that are the same as natively defined in KBL framebuffer 0x59160000; sure, it's harmless but why don't you try a more basic config?

AAPL,ig-platform-id        00001659        DATA
framebuffer-patch-enable          1        NUMBER
framebuffer-fbmem          00009000        DATA
framebuffer-stolenmem      00003001        DATA
framebuffer-con1-enable           1        NUMBER
framebuffer-con1-type      00080000        DATA

 

Your issue may also come from the use of kexts that I don't believe required: CpuTscSync + ECEnabler; I would recommend you disable/delete them.

[cinoyter]

Merci Hervé.

I tried your suggestions without success. For the display settings, I had taken the configuration from here mostly.

 

In the meantime I have also tried disabling VT-d, wireless and bluetooth but this also hasn't changed the outcome. I also tried the other device ID (00001B59) but this also didn't change anything.

 

Most of the time when I look up this symptom (grey screen with cursor) on the Internet, the response is "read Dortania's guide closer". But when I dig into it it mostly seems like the grey screen is often a symptom of a misconfigured graphics setup. Many people seem to have success with this particular device but it seems that few people have the HiDPI screen.

 

Thanks

[Hervé]

Try and inject your screen's EDID.

 

If you've not done so already, I also suggest you patch your BIOS to increase DVMT size to 64MB or 96MB. It's explained in our FAQ tuto on the matter as well as on that Git repo you followed. You'll then be able to remove the injected properties that restrict fbmem to 9MB and stolenmem to 19MB. You would no longer need them and would gain 4K output alongside.

[cinoyter]

I injected my EDID with the hex data obtained via NirSoft's "Monitorview", I removed fbmem and stolenmem from config.plist, and I executed setup_var 0x795 0x2 and setup_var 0x796 0x3 in a modified GRUB shell that I added to my installer USB key's EFI partition, and unfortunately, it still doesn't work. So perhaps my theory is incorrect...

 

Is there another obvious thing to try? I have attached the current state of my config.plist.config.plist.zip

[Hervé]

You do reset NVRAM from the OC Picker after each config change, right?

[cinoyter]

LOL sigh, I guess I'm a moron. I reset the NVRAM, immediately the text in the OpenCore picker was way smaller, etc. So who knows which one of these changes fixed it!

 

Thanks for your help.

[Hervé]

Problem fixed? Grey screen no more?

[cinoyter]

Problem is fixed, no more grey screen.