I'm using Asus RTN66U and 378.55.3-HGG-Final and I also can't find adaptive QOS...
The RT-N66U and the RT-AC66U share common chipsets and thus the cpu power requirement is deficient for both.
You didn't notice that this page is generic and it has a warning saying "features are model dependent"?
Sent from my Nexus 9 using Tapatalk
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