Old thread but anyway I solve the ahci problem by booting into safe mode. It loads the missing drivers from the installation. That info did squat for this machine though. I was going to update the bios as I saw they had newer ones supporting various things such as ivy bridge and linux compatibility but none of them would work. Appearently these "asus" crooks dont provide those updates for the bios the machine currently runs. It may be the chipset does not support it but they show up for the same model g3610. I have yet to get anywhere and maybe the reason this thread ended like it did but I will keep looking into it.
Looking a bit into linux threads on ways of getting it to use the uefi. Thats my thought anyway. Will have to look some more into the chipset as well to be sure.