Daniel- yes, all six GPU work fine independently but windows 10 does not see them all when plugged in together.  It will only see up to 5.  GPU seems okay, it’s a brand new 1200 w platinum evga. I also tried completely wiping the GPu drivers with DDU and still no joy. 

I’m starting to think this may be a windows 10 problem.  I may reinstall.

Thanks for all the suggestions, please keep them coming!