https://bitcointalksearch.org/topic/avalon6-safety-or-how-i-burnt-my-avalon6-1336377
Avalon
1. does the fan to the avalon come on?
2. does the fan to the psu come on?
3. using one psu plug it into the side that you see green lights from the board. (psu 850 will work for testing one board at a time).
4. psu could be bad.
Rpi
1. rpi connect to your laptop, and see if you can access it using a ethernet cable connected between the rpi and laptop
2. Is the sdcard bad
3. did the ip address change or internet settings?
I speak to you with common issues and may be able to help. My Avalon has what caanan say was a bad board. During the summer I blewout the outlet , fryed and could of caused a fire. Thought my board was bad and ignored messages from the miner status than said psu might be bad.
Bought a Avalon 7 plugged my psu in and same thing nothing powers red lights couldn't believe another bad board. Well looking carefully at the psu noticed that 1 of the 2 pcie cables was melted and stuck plugged into the psu.