One.To avoid the unfold of virus from the firmware, which may result in harm to the ANTMINER S19 collection, the placing operate of “Secure Boot” continues to be switched on and also the “Root Authority” function is disabled. If you haven't acquired your refund nonetheless, please Check out your Paypal https://bitmain-antminer-s21e-xp74952.tinyblogging.com/bitmain-antminer-s21-pro-fundamentals-explained-78232964