I tried just changing the stepper drivers to start with. When that failed, I changed all the whole arduino Mega+Ramps. I am at a loss as to what this problem is now. The print stopped about 40 minutes on this last print. I have replaced all the electronics & still have the same problem. I also replaced the P/S with the same Mean Well NES-350-12v. I have checked all the wires & connections, but maybe I have a bad connection somewhere that I missed. I am also using the Marlin RCBugFix firmware.