It looks like the "Temperature Display with time/fan monitor/overheat and fan failure alarm" is functionally something like the controller part of this Multi-Auto Controller click here#. If I'm right, the 3-pin connectors are power to the fans. The additional HDD LED connector is still a mystery though. I can see that I'll have fun experimenting, but I think I'll use a spare CPU cooler first and let the motherboard look after the real CPU cooler. I wonder where the controller gets its power from.