@pastrychef , I share my experience of installing Opencore Bootloader on the Asus ROG Strix Z370-G. Basically I had success on the first attempt via your premade zip folder “EFI OpenCore 0.6.1 Z370G” but there were a few learning points which may help others trying this. I am not genius-expert so if this explanation is long and simple, that's where I am at.
A) I wanted to do a fresh OSX install onto a new 1 TB Samsung 860 EVO drive. I was creating this via my existing Hackintosh which was running Mojave with Clover bootloader. To create the USB installer, I followed the quite clear techy directions at the Opencore site which is
also where I downloaded the utilities mentioned:
https://dortania.github.io/OpenCore...ide/mac-install.html#setting-up-the-installer
B) This was a little different from the way I had previously made Clover installers with the Tonymac tools. For one, I used a few command line tools in Terminal, that all worked surprisingly well. I used the
GibMacOS utility and ran the
gibMacOS.command to download the entire 6GB+ macOS installer, once complete I ran the
BuildmacOSInstallApp.command. This generates the same kind of installer that you would get if you downloaded via the Apple store and the image should be put in the Applications folder, to simplify the next step of using the
createinstallmedia command.
C) Next I formatted the USB drive via Diskutility to prep for both the macOS installer and OpenCore. I used macOS Extended(HFS+) with a GUID partition map (not APFS). Created 2 partitions. The main MyVolume and a second called EFI which is used as a boot partition where your firmware will check for boot files. Next I ran the
createinstallmedia command via Terminal.
D) I now had a USB drive with the OSX Installer on it and an empty EFI folder on it. I used the
utility MountEFI to bring the (empty-USB) EFI folder onto my desktop. I downloaded the linked files you provided called “EFI OpenCore 0.6.1 Z370G.zip.”
Once opened, your Z370G EFI folder contained two folders “BOOT” and “OC.” I dragged a copy of “BOOT” and “OC” from your Z370G EFI folder into the empty EFI folder on the USB installer. Now, at least in theory I had a bootable Opencore+Catalina installer. I knew that I
still needed to edit my config.plist with info specific to my hardware but I tried booting the installer anyway. To my (slight) surprise, the OC USB Catalina installer booted rather easily and I ran the OSX installer onto my new 1TB Drive. The installer ran to completion and OSX booted normally through the usual startup screens of a fresh OSX installation.
Generally, this seemed a success!
E) Now, I wanted to make the 1TB drive bootable without the USB installer. I used
MountEFI to open the 1TB EFI folder and it contained 1 folder called “APPLE.” (The Apple folder contains a file called “Firmware.scap” which can be ignored and is only for Apple OEM updates.) I took the same copies of “BOOT” and “OC” from the Pastrychef Z370G EFI folder and dragged them into the 1 TB EFI folder. So now I had a 1 TB drive with Catalina installed and a Z370G-specific EFI folder on that drive with “APPLE” “BOOT” And “OC.”
F) All that remained was to open the “OC” folder on 1 TB and make the changes in the
config.plist specific to my Z370G hardware. I had to remember that I couldn’t just edit the config.plist inside the EFI partition. I had to make a copy onto my desktop, edit it, then delete the one inside the EFI folder and replace it for changes to take effect.
G) There are only a few data strings in
config.plist that need to be changed specific to my particular Z370G hardware, as noted in Pastrychef’s README. They are the
motherboard serial, the
ROM data (MAC address), system product name (iMacPro1,1),
SystemSerialNumber, and
System UUID. I was stuck for a moment but I downloaded the
utility GenSMBIOS-master which is a collection of scripts that generate this information particular to your personal hardware. It was extremely helpful and immediately generated nearly all of the information required.
H) The one thing that was a bit of a learning curve was putting in the MAC address (this is your network hardware address.) The MAC address is often referred to as a burned-in address (BIA) because, historically, this address is burned into ROM (Read-Only Memory) on the NIC. This means that the address is encoded into the ROM chip permanently - it cannot be changed by software. If you look up your MAC address under preferences > network > advanced > hardware you will see a data string like: 97:A1:C1:E3:36:F1. This is NOT the format you want to use when you put it into the
config.plist. If you do, it will boot, but generate an OC error message in the process. The correct format for the
config.plist is without colons and spaced properly so if your Mac address looks like "97:A1:C1:E3:36:F1" it should be put in
config.plist as: “<97A1C1E3 36F1>” -- and if that seems confusing or tricky, you can try using the
tool ProperTree to make sure your
config.plist is correctly formatted. Propertree is a free cross-platform GUI plist editor written using Python. Once I had all those set, the installation booted from 1 TB without errors and all OSX functions seemed pretty immediately OK. I had to set system preferences > sound > to internal speakers. But that was it.
OBSERVATIONS AND PROBLEMS:
I.) Running with the opencore bootloader, I can’t access the BIOS screen at boot via holding down f2 or “delete.” Holding down either key, I just get a black screen that eventually yields the OC boot choices. If I disconnect all drives (no SATA devices) and boot with f2 or “delete” then the BIOS screen appears as you would expect and changes can be made and saved. This is not a deal-breaker but when I check online it seems a known bug and others online have noted it and freaked out. I tried adjusting the BIOS to a longer POST time (5 seconds) but this had no effect. Also, I then removed the 1 TB Opencore drive and tried booting with one of my older 250GB/Clover/Mojave drives and also failed to get into BIOS via f2 or “delete.” Strange! So I am not sure whether this problem arose with OC or what. Seems odd, and is possibly connected to my next SATA problem:
II.) If I boot from the 1TB / OC / Catalina drive with any other SATA drives attached to the system that are older (i.e. a 250GB/Clover/Mojave drive) then Opencore boot loader comes up and "sees" these other drives at the startup OC boot selector screen but after boot into OSX they are no longer visible. I tried to find and mount these drives with diskutil and diskutility, but nothing is available to mount. Even if I connect one externally via a USB port it is not mounting. I am wondering what I need to change to fix this and have drives mount? Is the problem that these drives have EFI partitions with Clover in them? Or a general SATA issue?
III.) I think some people have managed a dual-boot system where if they have 2 drives in a system and one has OC bootloader and one has Clover bootloader they can boot from either. I am not sure how I would set that up because as of this moment to me it looks like there is not great compatibility and if you have 2 different bootloaders on different drives they have to fight for the GUI??
Any advice or ideas appreciated. I could post my clover config.plist and my opencore config.plist if that would help.