If your motors don't lock,
do you hear any hiss, ticking or clicking from the board or motor? The Hobbycnc boards have an audible chopping frequency. Even the new boards have a tiny amount of it, you have to listen carefully.
Have you checked your Vref? You must set the current on each motor, otherwise, if you have your potentiometer turned all the way down or too low, you will not have enough current to lock the stepper.
Is your LM317 getting REAL hot? I forget the placement number on the board for the LM 317, but it is by the fan connector. A hot 317 will indicate you have a (more than likely) bad solder joint in the power supply section of the board, at least in my experience.
Try these things, and let us know.
EDIT: Also, which step rate do you have selected on the board? If you don't have all the "J" jumpers installed correctly, then you can't check the Vref or set the microstep rate (1/2,1/41/8 step), etc.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
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