Solved Replaced RAMPS, now steppers are jumpy

I'm trying to resurrect my R1 after not using it for a while. Last time it was working fine, then it wouldn't extrude on E0. Through toubleshooting, I narrowed it down to the RAMPS board: I swapped stepper drivers and motor outputs until I resolved that the motor worked on other outpots, and the driver worked on other outputs, but nothing worked on E0.

I had a spare Sainsmart RAMPS 1.4, so I carefully transferred every cable and driver over to it. So now all motors work, but they're jumpy. I use my controller to tell it to move 1mm, and it moves a small bit, but makes a medium-pitch noise. I tell Z-Axis to move 1mm, and it moves 5-10mm very quickly.

I *think* that I need to calibrate the A4988 stepper motor drivers, but I don't get much of a difference by adjusting them, and Vref is 400-500mV on all of them. I was very careful not to bump the potentionmeter when transferring them.

Could the new RAMPS be causing this, or is it something else?

 

SOLVED!
I was browsing through the newest troubleshooting posts to see if I could lend a hand, and came across this post, which lead me to this post. I realized I didn't transfer the jumpers under the driver boards from the old to the new.

Thanks to @mark tomlinson and @Geof!