not booting. I don't know what else to do !

[IvanDragoPC]

at the opencore boot picker

Nothing, didn't work I tried 10.15 but nothing seems to work :/

 

[wstrohm]

I tried 10.15 but nothing seems to work :/

?? 10.15 is MacOS Catalina, right? Thought you were trying for MacOS High Sierra, 10.13.6 (latest High Sierra).

 

[wstrohm]

In your config.plist:

1. In Booter/Quirks/EnableWriteUnprotector you have Value = YES; the guide says NO. But see this:

2. In Kernel/Add/3, you have Enabled = YES. If I look at EFI/OC/Kexts/UTBDefault.kext/ShowPackageContents/info.plist/IOKitPersonalities/XHC1, I see no USB ports listed. Is that correct for the UTBDefault.kext contents? There appears to be no USB port mapping in that kext (but I am not familiar with UTBDefault.kext so not sure).
3. In Misc/Security/SecureBootModel, try changing the Value from Default to Disabled. It could help with:

I've loaded everything on a USB drive and getting the same error.
34:482 00:011 ASSERT [OpenCore] ImageLoader.c(986): ((BOOLEAN)(0==1))

based on this note in the guide. (In link, scroll down to "Stuck on OCB Image Failed".)
4. In NVRAM/third item/Value "npc=0x3000" may not be needed... see the image from the guide below:

5. Re-read the "AMD BIOS Settings" area in the guide... maybe could help.