Coincidentally I'm planning on doing the same thing in the future. I want to use the fan controller to get airflow going through my home, because it would allow me to buy a decentralized ventilation system, which is much cheaper than a centralized one, much more energy efficient, much quieter, and no need for ducts or filters.
I have an external adapter for a USB to IDE/SATA controller (brand: Flypower), which has a Molex attached to it. On the back it says Output: 12/5V 2000 mA.
I'd like to combine the fan controller for instance with four 120 mm Scythe Slipstream fans that have a max of 1600 rpm, 33 dBA, 150 m3/h and 0,41 A. They would probably never run at their max speed. I don't know how much power the fan controller itself takes up, but in theory the external adapter has enough capacity with the 2 A.
I've tried an adapter I had lying around for an external HD and rewired it into a MOLEX connector. It's rated at 33W/2.2A/12V, and manages to power the Kaze Server but only at 1/2 RPM.
That's weird. I don't know how many fans you have running and at what rpm, but the adapter should be able to power the fan controller and fans. Have you tried with the LCD screen turned off?