Operators frequently ask whether sub-0.05 TH/s units make sense for a home garage. Our answer is usually no — but the reasoning is physical, not ideological.
Power Supply Overhead
Smaller air-cooled units still require a dedicated outlet, surge protection, and ventilation work. Fixed setup costs do not shrink proportionally with hash rate. When we model Korean residential rates near ₩120 per kWh, a 0.03 TH/s machine often spends more on infrastructure than it returns unless power is exceptionally cheap.
Noise Per Hash
Compact miners spin smaller fans at higher RPM. Decibels per terahash tend to be worse on entry units. Neighbors notice a 0.04 TH/s box on a shared wall as readily as a larger one.
When Sub-0.05 Still Makes Sense
Educational setups, warranty testing before scaling, or sites with free industrial power may justify smaller units. We document those cases in bench reports rather than recommending them broadly.
The 0.05+ Sweet Spot
At 0.05 TH/s and above, air-cooled designs from major manufacturers typically include heat sinks sized for sustained operation and fans that survive Korean summer intake temperatures when the room is ventilated correctly. That is where our review work concentrates.
If you are unsure where your planned purchase falls, send model numbers before you buy. A 45-minute advisory call costs less than restocking fees.