Got the HAPP power supply in, and it too showed low voltage... after some checking, it looks like the coin slot bulbs are causing the voltage to drop. Which seems, not gud. Disconnected them and I'm getting close to 12v with the HAPP and just over 10v from the original PSU. However with the HAPP, even with the potentiometer cranked all the way down I'm getting close to 6v on the 5v pins. So I think that if I had the original at a similar setting (it's setup almost dead on at 5v) the 12v line would be more or less the same.