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Well at the cheap end then I'd look at Roy's boards at DIYCNC they are ok for the money and I've used many of the opto boards. At the other end then and by far the best BOB on market for the money is...

Wait, give this a go first, if the velocity / accel in Mach3 is set too high the motor will stall, put the setting back to 2, fit the motor to the machine and reduce the velocity and acceleration...

Correct, there is a table printed on the PCB showing the options.

Yes, so a setting of 1 will give you the maximum torque, any higher will give you less torque and the reduction can be dramatic. The downside is you will loose accuracy because the smallest increment...

It looks like you have this setup;

3163B Stepper Driver
set to;

Dynamic Current = 2.5A
1/8 Microstep
50% Standstill Current

57HD5401-14S/8 Stepper Motor