Thanks for suggestions. Now It works.
At the moment I manage to boot only with clover, inside usb installer.
I have installed clover on installation disk without result.
Doesn't clover support apfs/mojave yet ?
Let me know.
HD7750.
To try, I initialized disk, repeated installation and put dsdt.aml in EFI/Clover/ACPI/patched: Is It the right folder?
Now the screen is whole yellow: a little step ahead...
Thanks for reply and modified dsdt.
The video card is in 1x slot cause in 16x slot the pc rebooted by itself.
Anyway, now I get screenshot in attachment.
I get black or yellow screen after verbose boot.
I installed Olarila Mojave 10.14.1.
I attach my original dsdt.
Let me know if you need more information.
PS: Where do I have to put modified dsdt?
Send me iMac-of-preben.zip