I went out and bought a thermaltake xcontroller which I think may be faulty.
I have 3 fans connected on 3 seperate channels, but I am finding there is very limited room for fan speed adjustment. For example, if I set one of the channels to the minimum voltage, then turn the knob a fraction it will light up green, then turn it a fraction again, and it will light up red. After it is red I can turn it about 270 degrees to max.
Is this the normal behaviour for this fan controller, or have I got one which is faulty?