I have four 42BYGHM809 http://dlnmh9ip6v2uc.cloudfront.net/...42BYGHM809.PDF stepper motors all driven with four A4988's.

How do you calculate what PSU i should get? the A4988 can take 2A and 35V but i have not a clue how this translates to the 1.7A/phase and 3.06v for the spec of the steppers?

based on the driver i would have comeup with a 35V 8A PSU? but im sure its not that easy?

Thanks for looking