Bitmain Antminer S21 Pro (220Th)

AsicProfit Support AsicProfit · 2026年10月12日

Owner reports vary by batch. Some farms see low failure rates and others report fan, power supply and hashboard problems within months. Fans and power supplies are the cheaper, easier fixes. Bitmain's shop gives 365 days of warranty from shipping for the original buyer, while resellers set their own terms. Keep intake air clean and within minus 20 to 45 C to reduce failures.

AsicProfit Support AsicProfit · 2026年10月8日

Your electricity price matters most. The S21 Pro uses about 3.5 kW, around 84 kWh a day, so at high household rates power can eat most or all of the earnings. Owners in expensive-power countries often host abroad or wait for cheaper tariffs. Put your exact rate into the calculator above. Reusing the heat in winter can also change the sums.

AsicProfit Support AsicProfit · 2026年10月6日

For most homes, yes. Bitmain rates it at 76 dBA at full fan speed, with up to 550 CFM of airflow. That is far too loud for living space, and it runs around the clock. Owners put it in a garage, outbuilding or ducted room, or use shrouds to send the hot air somewhere useful. Any enclosure must still let it breathe, or it will overheat and throttle.

AsicProfit Support AsicProfit · 2026年10月5日

It needs single-phase 220 to 277 V at up to 20 A, so plan a dedicated 240 V circuit. Standard 110 to 120 V outlets will not work. Bitmain includes a C20 power cord with the S21 Pro. Have an electrician fit the right receptacle and breaker for a continuous load of about 3.5 kW. Do not use extension cords or power strips.

AsicProfit Support AsicProfit · 2026年10月4日

They are the same machine in different bins, both rated around 15 J/TH. Bitmain's current spec lists 245 TH/s at 3675 W, 234 TH/s at 3510 W and 220 TH/s at 3300 W. The 245T draws a little more power for a little more hashrate, so the better pick depends on the price gap. The calculator above compares them at your electricity price.

AsicProfit Support AsicProfit · 2026年9月16日

Not exactly. Owners comparing the two report that both use the same generation of chips, but the boards and chip counts differ. The S21 Pro is air cooled on single-phase power at about 15 J/TH. The Hyd versions need three-phase power and a water loop, and push more hashrate per unit. Choose based on the cooling and power you can provide.