Hey Tiiii86,
This is the official Gigabyte/Aorus account and your post made us want to create this account so that we can try and help people like you, so kudos to you for pushing us to take the right steps and to @Fiklm for pointing out the right steps there
We have looked into the issue you have encountered and would like to offer you a possible solution.
04 refers to South Bridge initialization before the microcode loads so it is not an error code.
D4: Please disable the fast startup to solve this issue.
Path: Control Panel > Hardware and Sound > Power Options > System Settings
A0: It is normal after booting up.
Please let us know if your problem persists.
PS: Oh and sorry about writing in English, we will get that fixed in the near future.