How many max amps per motor w/ HobbyCNC board?

[chozo]

4AUPC Chopper Driver Board Kits 3 or 4 Axis Unipolar Chopper control. NO "Ballast" resistors required! Individual OR simultaneous control of 2/4 Phase Stepper Motors. Accepts 5, 6, or 8 wire stepper motors only. 44VDC maximum input voltage, 12VDC or 24VDC minimum input voltage depends on fan voltage used. 3.0 Amps Maximum per Phase, 500ma (.5A) minimum. Adjustable throughout this range.

So, does this mean, if I used 3 motors, they could only be run at a max of 3 amps each? What if one motor is less than 3, can the others be more?
Is it possible to use a motor with a 4 amp rating?

Also, does the voltage rating on the motor matter?

Any help is appreciated.