I landed ten including their power supplies direct from Canaan during their flash sale. They arrived yesterday. Opened five up, removed 2 dragon mints and 3 s9s and replaced them with the 921s and their corresponding psus , no life. Tried 250v power, 220v power and 220v power through a pdu. Controller and auc’s light up, but no one is home on the 921s. Power supplies power on and blow air as they should. Last step will be trying my bitmain, halong, and hp power supplies. Canaan has been more than helpful though via video calls on WeChat and remotely logging in via team viewer. It could be possible these were shipped with no firmware as my controller did not have firmware installed either.