We take full responsibility for the problems caused and had not anticipated the unique loading conditions of a miner when selecting and testing the suitability of these power supplies.
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We are sorry for the inconvenience you may have experienced regarding power supply failures, or even sporadic events of smoke from our first batch of Antminer S4s. We immediately set out to investigate the reports of failed power supplies from customers, and have made immediate changes to improve the quality of future deliveries. What happened with these power supplies is not acceptable.