Hey,
After I managed to boot iAtkos, I opened Disk Utility to format the partition so that I can install the OS on it, but it says it's unable to modify partition map and cannot erase the partition. I changed "IDE" to "AHCI" in the BIOS.

Here is a video about the problem: Cannot format FAT32 partition as Mac Journaled - How can I get it work? - YouTube

How can I get this work?

my config:
GIGABYTE GA-870A-UD3 rev. 3.0
CPU: AMD Phenom II X4 955
4 Gb RAM
ATI Radeon HD 6870