1: buy a 27" AiO iMac
2: buy a EFi-X 2.0 module
3: use the knowledge of the OSx86 community
4: use ASUS EFI Firmware

- for the first solution you need a lot of money
- for the second solution you need less money but
a screw driver
- for the third solution you need this community
- for the fourth solution you need?

That`s the question!

Has anybody tested the ASUS P5QE mainboard series with
the ASUS EFI ?

Could it be possible, that you only need a USB- Stick
with the flasher software to change the BIOS- Software
against the EFI- Software?

And of course you have to format the S-ATA HDD as GUID?

And of course you need only a copy of the original OS X
Snow Leopard?

Would be nice to hear something from the community.

Your PC-Mainboard's EFI Firmware is not compatible with the one used by Intel Macs, and even if you would succeed to modifiy it accordingly (I think it's theoretically possible - but a guru job. ), you would still need the SMC device - at least the part that's necessary to enable OS X's binary-decryption.
Résumé: You'll still need at least a Snow Leopard capable EFI-bootloader (Chameleon, PC_EFI, ...) & fakesmc or a decrypter kext, to boot a Retail DVD / system.
There are even How-Tos made for your hardware out there - check google.

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