20% is relative to their particular tested CPU, HFS, and motherboard. Testing method can be found on Intel Developer papers as well as various Thermal Design Guides. My guess is Intel now realized 130+W CPU combined with
150W PCI-E graphic cards is a little too much for their proposed little PC case.
Since these info was from a "Forum" (IDF = Intel Developer Forum) and most of these data/testing results are from their online library, if Intel want me "Do not reproduce" as stated on the booklet, I guess I will nont have any kids then

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