lol sooooo who is the dude saying its a good idea to hook these to a car battery?? i told a guy before its not a good idea to hook them to a car battery to blow the fets that are failing so the board can boot back up again....i dont feel like going through page after page to find my older posts in this thread but to recap my later comments.....dont reverse the inputs (keep ground to ground and pos to pos dont put pos to neg and neg to pos) and if you want to blow the fets of board that look like they are dead even after verifying the pumps work and the thermal paste is good then use a server psu with 2 wires hooked to it that wont shut off like the cointerra psus do and pulse the psu on for a second or 2 then off for a second or 2 then on again and off again until the fet fully blows leaving a clear indication of which one is bad and needs to be replaced and or lets the board at the very least power on again and more often then not hash again but it will be slightly slower because the fet powering the die will be blown so for each 2 fets top and 2 on the bottom goes to 1 die so if 1 of the fets blows in the group 1 die will be down until its replaced. u want to pulse the power not just turn it on and let it burn because they get white hot in a second or so and will burn through the multiple layers of the board pretty fast. i had people send me their broken boards to do this and or replace the failed fets if they didnt have the tools to do it since i do so if u have dead looking boards with no lights and no char patches give this a shot and see how it works for you and if you have boards with gree lights but only partially hashing i can replace the fets on the board for u just pm me if interested but to get most boards back up and running this is what u do....not hooking a 12v car battery to the boards....i wonder if it was the same dude that sent me his boards to be fixed and that i told him a car batter wasnt a good idea lol.