Gecko servos

Hi All!
Ok! I could figure out the pins on the pcb for the harris
chipset,A,B,+ but the ground,after playing with it for while I've
gave up!,got more important things to do.Anyway thank's a lot!
Now,i've a 1/2 stepper system on my minimill and a 5mm pitch
Aprox.0.200" lead ballscrew and i've being thinking about upgrade it
to the GECKO servo driver.
What's the specs. for the Gecko servo driver?
and what would be the performace using a 0.200" lead ballscrew
what about computer power?(486,586,P2)necessary for let's say
50"/min.using the same lead screws and 500 cpi encoder X 4?

I'm just trying to compare to what I've now and if it worth the
money to buy a new set of servo motors, and drivers.