[QUOTE = "Daranski, Post: 2131279, Mitglied: 2368107"]
Das wird dann der Grund sein. Wie greife ich auf OSX auf der Festplatte zu, um die EFI zu ändern, wenn ich vom USB-Installationsstick starte?
[/ZITAT]
1. First of all let the installation complete with the cleaned stick.
2. After the installation, start with the cleaned stick via F12 and select MacOS Catalina on the internal HDD / SSD.
3. Remove the radeonboost.kext from the directory cover/kext/other e.g. with your Clover Configurator.
That´s it!
P.S.
I had already reported this in post #21615. Do not know why it was not included in the installation instructions on the main page regarding the upgrade to MacOS 10.15.5.
This concerns the combination of the Radeon RX 5700 XT graphics card (actually all graphics cards with Navi Chip) and the current radeonboost.kext when upgrading to MacOS 10.15.5.
By the way, everything (all references) can be found in the german Hackintosh Forum.
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