OK calm down, yes, don’t just randomly order a new Arduino 🙂 . They don’t go bad all that easily and are are pretty simple. The RAMPS board is also pretty simple. If the stepper motor sets are moving opposite each other (which is actually them rotating in the same direction) then you have an intermittent wiring problem. It can’t be any other problem, right? They are both connected to the same stepper driver but just have one set of coils reversed. Can’t be a software problem or Arduino/RAMPS problem or even a motor driver problem.
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