Magic Smoke from RAMPS board on prusa i3

I was checking the voltages on the stepper drivers when I accidentally shorted something out, causing a little puff of smoke. The bed and extruder still heat up but nothing moves now. What all do I need to replace? Just the RAMPS board or Arduino as well? Also, the LCD is blank when just powered by the power supply but works fine when I plug the USB into my computer. Any help is appreciated, as I need to get it back running ASAP!

Worse case: all the driver modules and the mega

Best case: just the driver you where working on and the mega (since that's where the LCD power issue comes from)


Megas of course come blank, you will need to put firmware on it.

So mega for sure? There is no visible damage on it and it powers up just fine when I plug only the mega into my computer. But in any case, a new mega and ramps 1.4 should fix the problem?

remove all driver boards and see if the display comes to life, if you have a shorted driver, it will show a blank display.
If display now works, switch off power and try 1 driver at a time.