First 3D Printer (i3 Prusa) build Disaster :S (5 replies)

With hindsight perhaps I should have asked for help before trying again.
Now I have burnt 2 sets of electronics...Melzi and Ramps 1.4 (Arduino Mega)

I got a Pangu i3 Prusa kit and the initial Melzi board I fried because -/+ was swapped. Fine that was on me. The explosion was well like popcorn.



The second attempt I got a Ramps 1.4 kit and 4 stepper drivers.



I followed the instructions to the letter this time and made sure red was positive and blank negative.





After switching it on I saw some smoke and immediately switched it off.

1. Will all the electronics be gone?
2. How do I find out what went wrong?
3. Can the PSU be the cause?



At the moment I feel like throwing it in the trash but I should at least find out what went wrong.

Any experts have any ideas?