2. When the EEPROM NG is shown to the LCD screen of the hashboard tester, Look at whether the welding of U5 is typical; 1. Pay attention towards the system when replacing the chip. There'll be no obvious deformation on the PCB board following changing any extras. Check out https://antminers19hashboard42985.yomoblog.com/37876827/everything-about-s19-hash-board