If that radiator fan for the kuhler has a 3 or 4 pin plug, I would plug it into the cpu fan port. Maybe the board won't post to protect the cpu from overheating. It may need to detect some kind of fan.
... Got it figured out ...there's 2 CPU fan headers and BOTH have to be disabled. I assumed since the one was not active didn't need to be deactivated in HW monitor.
Every ones happy now.