I have a Goodman furance that I have replaced the motherboard 3 times they last about 6 months. Every time it happens the board blinks 3 times which means a vent issue but when I check the switch current its correct. We do have power outages. I also noticed some discoloring were the plug(runs from board to a pigtail then to the sensors) fits to the side of the board. I'm tired of the tech coming out and saying I need a new board not sure why it blows.

You better be putting a shunt/surge device on your main electric power line since it seems to be causing most of your problems. Discolored wires mean a loose fit or bad connector and that also needs to be fixed.