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#11
Now that is a blow my ACPI is in Power Management but I guess it is a different brand BIOS.
Well assuming the rest of the BIOS headings do not have anything that looks remotely like ACHI or the other settings I mentioned all I can suggest now is to go through all of those headings and just open up and see what there is - I have added another pic if it looks anything like yours try the ones I circled one by one taking care not to change anything. If we get nowhere then we can always ask the others. I just cannot see why the ACHI is mentioned in that link I sent and yet cannot be found.
Look I really am sorry this has dragged out and I cannot think your board is that old it does not have ACHI as a setting.