Why is my Antminer S9 only using one Chain
Also posting as an answer: the issue is that the GH/S (RT) on board 6 and 7 is 0--it is because the power quality coming into that dedicated power supply is too low.

The board has an ideal measurement (~4TH/s), no busted ASICS. After doing about 3 days of testing, it appears that the power quality upstream of the ASIC boards is pretty important. Even if the power supply is powered on (and reads the appropriate voltage), it is sensitive to the amperage rating of its circuit (I use 2 PS's, one for the main board + 1 ASIC board and a second one for the 2 other ASIC boards).

By moving the 2nd power supply (the one powering the 2 ASIC boards) to a high capacity 20 AMP circuit, everything works. (although now I have a huge power cable running to my miners from a separate circuit). I had to have an electrician come and pull that separate circuit from my main.