MARA UCB 2100LTL – Universal Mining Control Board & Firmware for Antminer S19/S21 Series

A replacement control board for Bitmain Antminers, designed in-house by Marathon (MARA) and preloaded with its MARAFW firmware. MARAFW provides auto-tuning, overclocking and underclocking, cooling profiles, chip-level monitoring and thermal protection, and works with fleet tools such as Foreman, Awesome Miner and BTCtools. The LTL version includes a lifetime licence, so no developer fee is charged; the version without it carries a 2.0% developer fee.

Compatibility

• Antminer S19j, S19j Pro, S19j Pro+, S19 XP, S19k Pro
• Antminer S21, T21
• MARA advises checking the list on the board's package for the exact models it supports

Specifications

• Model: MARA UCB 2100, LTL (lifetime licence)
• Firmware: MARAFW, preloaded
• Mining pools: no restriction; several pools can be configured

Notes

• The board runs MARAFW only; other firmware such as Braiins OS or Vnish cannot be installed on it.
• It can run a miner with one to four fans or none; fan simulators are not needed for immersion or inline-fan setups.