I want to report a little frustrating experience I had with my ramps... at some point the stepper motor was not working anymore properly, like they had no enough torque...some noise and little random movement .
So i tried ne stepper driver , recable ecc... no result, but then I accidentally pressed the button reset and.. Yhee ! Now they work again !!
So if you have this kind of problem, just press reset ( on the side of the RAMPS) reconnect and go
But I still have this problem quite a lot, usually happen on the end of a print...

Ciao !