AntMiner S3 spec and efficiency Since the S3 churns out 478GH/s (5%) and consumes 366W, Bitmain says its power efficiency is 0.77J/GH at the wall. It uses a standard ATX PSU, which is included in this listing Due to the relatively low overall consumption, customers can opt for an affordable mainstream power supply unit, although a PSU with a good efficiency rating is advisable. The whole unit measures 331 mm x 137 mm x 160 mm and it is cooled by two standard 140mm server fans, placed at the front and back. The AntMiner S3 is the company’s third generation bitcoin miner and it is based on the new BM1382 ASIC, which is a 28nm part. The BM1382 should offer a 20% power saving compared to the company’s old 55nm chips. This is Bitmain’s official spec for the new ASIC, which underwent testing earlier this month: