Bitmain
S21 Control board
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Antminer S21 Control Board is a next-generation control unit designed for the S21 series ASIC miners. It offers improved processing speeds, better system stability, and optimized power regulation. With enhanced firmware compatibility, it ensures smooth miner operation and reduced downtime. The control board is engineered to provide seamless communication between mining components, improving mining efficiency. It features heat-resistant components that extend the miner's lifespan and performance. This board is designed for professional miners seeking maximum stability and output.
| Specification | Details |
| Model | Ctrl_C76 or Ctrl_C81 |
| Main Control Chip | Amlogic A113D |
| Compatibility | Antminer S21, T21 series |
| Memory | 1GB DDR3 |
| Storage | 8GB eMMC |
| Dimensions | Approx. 100 x 90 x 20 mm |
| Weight | Approximately 0.3 kg |
| Power Supply | 12V DC via 6-pin PCI-E connector |
| Cooling | Passive (relies on miner’s cooling system) |
| Connectivity | 1 x Ethernet RJ45 |
| Fan Connectors | 4 x 4-pin MOLEX headers |
| Hashboard Connectors | 4 x I/O headers |
| Firmware Support | Upgradeable via SD card slot |
| Installation | Plug-and-play; ensure firmware compatibility with specific miner model |
| Release Date | 2023 |