MicroBT Whatsminer M66S (298Th): profitability and payback

What this rig is

MicroBT Whatsminer M66S (298Th) is ASIC. It runs SHA256ASICBOOST and draws 5,513 W: about 132.3 kWh a day and roughly 3969 kWh a month. Multiply that by your tariff and you get the power bill that arrives regardless of what the coin is worth.

An ASIC can only do its own algorithm. That is its strength — hundreds of times faster than a GPU — and its risk: if the coin moves to another algorithm or the network loses interest, the machine cannot be repurposed and can only be sold to another miner.

Before you buy

• ·Wiring and sockets. A multi-kilowatt machine is not something you plug into an extension cord: it needs its own line, and in an apartment block also the agreement of whoever pays the shared meter.
• ·Noise and heat. An industrial ASIC means 70–80 decibels around the clock and kilowatts of heat that have to go somewhere. Home-friendly options — hydro versions and sound-proof enclosures — cost more and need space.
• ·Used units and warranty. The secondary market is tens of percent cheaper than new, but the machine already has hours behind it: ask where it stood and count payback with a margin for repairs.
• ·Pool and withdrawal. Income arrives through a pool: it has its own fee, payout threshold and schedule. Before buying, check that the coin has live pools and which exchanges you can withdraw to.
• ·The date of the calculation. The numbers here are live, but they describe today. Network difficulty almost always grows — assume the real payback will be longer than shown.