Black Screen After Updating to Catalina

[EddyMac]

My wife's system is based on a Gigabyte GA-Z270N-WIFI board with a Core i5 7600K processor, using the built-in HD630 for graphics.

It was running the latest version of Mojave. Last night I decided to update to Catalina 10.15.4 using the installer app downloaded from the App Store a few days ago.

Update to Catalina was apparently successful but at some point in the game I lost graphics and it never boots to the desktop. It stalls for a long time and then reboots. Rinse and repeat.

The attached screen shot show the verbose output. It goes up to about 50 retries, then reboots.

I did some searching and found one suggestion that said to use the boot flag: -disablegfxfirmware. That didn't help much. It did give me a very brief look at the desktop as it finished booting, but then went black again. At least it did finish booting and didn't go into a boot loop as previously, but there is still some ingredient missing to allow me to have the screen back. I can VNC into the machine but that's not how I want to use the computer.

Any and all help greatly appreciated.

I am using the latest Lilu and Whatevergreen. I don't understand why the machine worked perfectly under Mojave but then I'm getting this black screen under Catalina.

 

[EddyMac]

Anyone? @pastrychef ?

SMBIOS is 18,1

 

[pastrychef]

Anyone? @pastrychef ?

SMBIOS is 18,1

Try adding "-disablegfxfirmware" boot argument to config.plist.

 

[EddyMac]

Is adding that to config.plist different than entering it as a boot argument at the clover screen (which I already tried)? As I said above, adding it as a boot argument at the clover screen does enable the machine to fully boot (as opposed to going into a boot loop), but still the screen remains black.

 

[pastrychef]

Is adding that to config.plist different than entering it as a boot argument at the clover screen (which I already tried)?

Adding from Clover boot menu should also work.

 

[EddyMac]

Adding from Clover boot menu should also work.

It doesn't.

 

[pastrychef]

It doesn't.

Try adding it to config.plist.

 

[UtterDisbelief]

It doesn't.

Hi there.

Well @pastrychef is correct and that command-line switch was the "official" as it gets fix, however try this one instead:

-nogfxfirmware

The problem is certainly linked to the closed source Intel firmware.

 

[EddyMac]

Thank you @pastrychef and @UtterDisbelief . I will try these when I get home tonight and report back.

What confuses me the most is why I had a perfectly-working setup on Mojave and then out of nowhere I get this problem when I update to Catalina.

 

[EddyMac]

OK so I'm now at home and have tried adding both of these boot arguments to the config.plist.
Results:
-disablegfxfirmware - same as adding it at the clover screen. The computer boots to the desktop with a black screen.
-nogfxfirmware - this produces the same result as in my original post. It has 50 retries, then kernel panics and reboots. Rinse and repeat. Verbose output is the same as in the picture in the original post.
Can any please help?