Antminer L3+ Profitability: Legacy Scrypt Math

At roughly 1.6 J/MH, the L3+ is about ten times less efficient than a current L9-class Scrypt machine and several times worse than an L7. On the same electricity, a modern unit produces multiples of the revenue, which is the entire reason legacy Scrypt hardware trades at scrap-adjacent prices.

Because Litecoin blocks carry merge-mined Dogecoin rewards, Scrypt revenue is more volatile than Bitcoin's — Dogecoin price swings move Scrypt hashprice sharply, which cuts both ways for marginal machines.

800 W is about 19.2 kWh per day. At ten cents that is $1.92 per day in power against the revenue 504 MH/s earns at current Scrypt difficulty — typically well under that figure. Break-even usually lands in the low single-digit cents per kilowatt hour.

Model it at three Dogecoin prices. Because merged mining rewards are a large share of Scrypt revenue, a Doge rally can briefly make legacy Scrypt hardware profitable, and a decline removes that just as fast.

Free, curtailed or behind-the-meter power. Heat reuse in cold months, where 800 W of quiet-ish heat replaces resistive heating. Parts supply for existing L3+ fleets, which remain surprisingly numerous. And learning Scrypt mining, pool configuration and firmware at low cost.

It is also a reasonable low-stakes platform for testing merged-mining pools before pointing an expensive L9 or L11 at them.

Ask for per-board hashrate from the miner's own status page, chip error counts, fan health and PSU type, and confirm whether the unit ran hot in a farm or gently at home. Nine-year-old boards fail at the chip level, and a machine at eighty percent of rated hashrate is common.

Pay parts-plus pricing, not nostalgia pricing. Budget for a PSU and fans, and expect to lose one board over time.

If Scrypt is the goal and power costs real money, an L7 gives roughly 9.05 to 9.5 GH/s at far better joules per megahash, and the L9 improves again. Those machines hold margin through difficulty growth that switches an L3+ off permanently.

We stock tested L3+, L7, L9 and L11 units with bench-verified hashrate and a limited functional warranty. Tell us your power rate and we will show which generation actually pays at your tariff.