Hi! Solved boot issue with a Samsung USB 3.0 pendrive.
Then I have done this in BIOS: CPU in C3 state, SATA to AHCI and overwritten Clover config.plist with the one on the zip file. Still I get the same stop after "unsupported CPU" and "unsupported PCH" statements and 1 minute of loading.
PS: I have an Nvidia Quadro 2000 graphic card.
Thanks again for your kind interest, Alex
I'm available for all tests that you need, if you likes
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After a lot of trial and error, learning and help from MaLd0n managed to get my (very) old system working quite well with Mojave.
Heres a sum up of what worked:
Reset BIOS Defaults, Set SATA to AHCI and C State to C3
Use Mojave Clover Image from Installation Tutorial, but edit Clover config.plist before installation and set SMBIOS to iMac 14,2 (I used a macOS Virtualbox VM for that)
Install Mojave as instructed on the guide
Install Clover as instructed on the guide, but change SMBIOS to 11,3 and enable Generate Pstate and Cstate at ACPI portion of Clover config
No need to inject any drivers for GPU, it works natively
It's a modest system but does the job.
I've attached Send me.zip. It contains EFI folder, config.plist, and other information that could be useful for anybody replicating a similar build.