Best Guess:

Putting a jumper between 1-2 resets the hardware without overwriting user settings.
Putting a jumper between 2-3 overwrites user settings with factory settings, then resets the hardware.

EDIT: Dude, I really feel for you if you can't get it working again. Tonight I moved my blade from office back home, and I had a heart attack for about 30 seconds, when I saw:

Chip: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx (hashing at 0 Mhash/s)

So, I decided it was a **** nightmare, and I cut the power off the PSU.

Then, closed my eyes, opened again, and put the power back on:

Chip: OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO

Allright. It was a nightmare indeed. Back to reality...

I hope it will turn out good for you too. Good luck!