I don't know about Mojave because it's old at this point.
Although it is recommended to use the MultiBeast Mojave version or the Clover Boot loader.
Now I am using only Opencore-based EFI. Verified ONLY by Catalina and Big Sir.
I made it by OC-Gen-X and then updated the OpenCore.
OpenCore Config Generator. Contribute to Pavo-IM/OC-Gen-X development by creating an account on GitHub.
github.com
Attached EFI is for a built-in graphics only.
Just put smbios information by using GenSMBIOS-master;
Generate SMBIOS by select 3 and press Enter
Enter SystemProductName as iMac15,1
After creating MLB, SystemSerialNumber, SystemUUID
Edit config.plist by PlistEdit PRO or OpenCore Configurator.
You can put it in PlatformInfo-Generic item.
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BIOS setting; only need -Boot-CSM-Disable
When the SSD is replaced or newly inserted, the CSM value is often changed to Enable.
If the operation is abnormal, you should check the BIOS value frequently.
* If you execute reset NVRAM at boot time, the BIOS boot sequence may be messed up, so be
sure to familiarize yourself with the BIOS update method before starting.
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About GT 740
I haven't tested it because I don't use external graphics, I believe the following articles will be helpful.
Nvidia GPUs
See Kepler Series(GK 106 Variants)
Needed kexts:
Nvidia’s Web drivers
Lilu.kext
WhateverGreen.kext
AAPL,ig-platform-id
04001204 Used when the Desktop Haswell iGPU is only used for computing tasks and doesn't drive a display
Various patches necessary for certain ATI/AMD/Intel/Nvidia GPUs - acidanthera/WhateverGreen
github.com
Add igfxmetal=1 boot argument (and enable-metal property) to enable Metal on offline IGPU
There seems to be a saying that iGPU should be enabled in BIOS.
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Opencore guide
Current supported version 0.9.1
dortania.github.io
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