Weird. I have a 4790k, but I doubt it is an issue of CPU generation. More like Motherboar BIOS.
I'll poke around and see If I can reproduce that wit BIOS settings.
EDIT:
On second thought, I don't think there are any BIOS settings that would prevent AI suite to not give you the option to use adaptive mode. It must be the software version or BIOS firmware.
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