My Kossel Mini used to work with the above electronics but it somehow failed to start up suddenly. When it is powered up, the LED1 on ramps blinked twice and there LCD no loner lights up. I tried to download the firmware again but my computer can no longer connects to it. Even I unplug all the sensors, motors, peripherals, the board is not responsive. I have also tried switching to USB power sourby kelvinlg - Reprappers