My Antminer shuts down after like 20 seconds.
I have tried everything I can think of.
Tried all wires I can think of to connect the green and black wires.
Tried paper clip and whatnot.
Tried running only 1 blade.
Tried cutting the green&black wires and connecting that way.
Tried several PSUs from 650 to 1250W
Anyone?

if your PSU and antminer turn on fine, then the PS-ON jumper isnt the issue (assuming it isnt randomly wiggling loose, but then it would cycle on and off a LOT!
sounds like the issue is your antminer if multiple PSUs cause the issue, but im not sure why. try switching the control board to the secondary hashing board and run only that side of the unit.
also, take a multimeter and measure the voltage at the screw terminals. if its outside of 11.8-12.3V you could be having issues