Bitaxe Gamma vs Antminer S21: The Honest Comparison 2026
By Dominik Lederer, Founder, Hardware Engineer & Solo Mining Expert · Updated August 10, 2026
In brief: The Bitmain Antminer S21 is an industrial Bitcoin ASIC with 200 TH/s at 3,500 W, while the Bitaxe Gamma 601 is an open-source home solo miner with 1.3 TH/s at 17 W. Both search for the same block and, if successful, both receive the same reward: 3.125 BTC plus transaction fees.
The S21 has 154 times the hashrate, giving it a significantly higher real chance of finding a block. However, it still loses economically: it burns 5.3 euros in electricity for every euro of statistical yield, whereas the Bitaxe burns only 3.95 euros. And the small miner even uses the newer chip generation.
What is the Antminer S21 and how does it differ from the Bitaxe Gamma 601?
The Antminer S21 is Bitmain's workhorse for data centers: 200 TH/s, 3,500 W, 17.5 J/TH. Official manufacturer values, not marketing estimates. Built for a hall with three-phase current, supply air, exhaust air, and ear protection.
The Bitaxe Gamma 601 is the opposite and yet the same idea: a single ASIC chip, open firmware, 1.3 TH/s at 17 W and 13.1 J/TH. It connects to a normal power outlet, without its own electrical installation. Here, it costs 129 euros as the Snowstorm Edition, according to product data 15 to 19 W, with power supply, 3D stand, and OLED display.
The interesting point is not the size, but what is left at the end of the year.
Who has a better chance of finding their own block?
Here I am uncomfortably honest, because this comparison is otherwise often fudged: The S21 wins. Clearly. With a difficulty of 127,479,855,693,691, the S21's solo chance is around 1:87 per year. The Bitaxe Gamma 601 reaches about 1:13,355 per year.
That cannot be debated. 154 times the hashrate means 154 times the probability of success. If you only ask "which one is more likely to find a block," you have to choose the S21. Period.
But that is rarely the only question. A chance of 1:87 remains a chance of 1:87, and in the meantime, it costs a lot of money.
What are the real annual operating costs?
Let's calculate with 0.35 euros per kWh, the realistic German household tariff. The S21 draws 30,660 kWh per year. That's about 10,731 euros in electricity costs. The statistical annual yield is about 2,030 euros. Ratio: 5.3 to 1. For every euro the device statistically generates, it burns 5.30 euros in electricity.
The Bitaxe Gamma 601 draws 148.9 kWh per year, which is about 52 euros. Its statistical annual yield is about 13.20 euros. Ratio: 3.95 to 1. This is not a business model either, and I'm not claiming otherwise. But it's a better ratio, and the absolute sum is that of a refrigerator rather than a small car.
Important: None of us have zero electricity costs. Anyone who tells you that is selling you something. Even with photovoltaics, electricity is not free; it has simply been paid for already.
Why does the small Bitaxe contain more modern technology?
This is where most comparisons are simply wrong. The Antminer S21 uses the BM1368. The Bitaxe Gamma 601 uses the BM1370, which is the newer chip generation from the same company.
You can see this directly in the efficiency: 13.1 J/TH for the Bitaxe versus 17.5 J/TH for the S21. The home miner is not technologically behind the industry; it is ahead per terahash. It just has one chip instead of several hundred.
For me as a hardware developer, this is the real appeal: the gap between "professional" and "home" has closed in terms of silicon; only the quantity is different.
Can an Antminer S21 be kept in an apartment?
No, and not by a small margin. 3,500 W generate the waste heat of a powerful fan heater running twelve months a year. The fans are industrial fans, loud enough to make staying in the same room unbearable. I deliberately don't give a fictional decibel number because noise levels depend heavily on the installation location. Qualitatively, it's sufficient to say: The S21 belongs in a hall or a detached adjoining room.
The Bitaxe Gamma 601, on the other hand, is a desktop device. 17 W of heat, a small fan, an OLED display with the Best Difficulty. It doesn't disturb a home office any more than a network hard drive.
S21 vs. Bitaxe Gamma 601 in direct comparison
| Criterion | Antminer S21 | Bitaxe Gamma 601 |
|---|---|---|
| Hashrate | 200 TH/s | 1.3 TH/s |
| Power consumption | 3,500 W | 17 W |
| Efficiency | 17.5 J/TH | 13.1 J/TH |
| Annual electricity costs | approx. 10,731 Euro (30,660 kWh) | approx. 52 Euro (148.9 kWh) |
| Block chance per year | approx. 1:87 | approx. 1:13,355 |
| Electricity cost per Euro yield | 5.3 to 1 | 3.95 to 1 |
| Suitability for living spaces | no, hall or adjoining room | yes, desktop operation |
| Purchase price | Industrial device, market price highly fluctuating | 129 Euro (Snowstorm Edition) |
Update August 2026
At the retarget on 08/08/2026 on block 961,632, the difficulty increased to 127,479,855,693,691. The Bitcoin price on 08/10/2026 was 56,404 Euros, making the block value approximately 176,300 Euros, depending on the exchange rate, as of 08/10/2026. All figures in this article are calculated to this standard. The reward itself remains 3.125 BTC plus transaction fees, regardless.
The following has changed: The block chances for both devices have slightly decreased compared to spring, and the S21's cost ratio has further deteriorated.
Solo mine without breaking the bank
Same block, same reward, 17 W instead of 3,500 W. Hand-assembled in Bavaria, ready to use.
"A miner that can't run in the living room won't run at all in the end. That's exactly why I build the small devices."
Dominik Lederer, Founder Polarblocks
Who benefits from which device?
The S21 makes sense if you have industrial electricity prices, a hall, a ventilation plan, and a pool. Under household conditions, it is an expensive misunderstanding.
The Bitaxe Gamma 601 makes sense if you want to help decentralize the network, understand the technology, and hold a real lottery ticket for 3.125 BTC plus transaction fees, without disrupting your household. It remains a very small chance. But it will cost you 52 euros per year instead of 10,731 euros.
Does a Bitaxe really get the same reward as an Antminer S21?
Yes. Whoever finds a valid block receives 3.125 BTC plus transaction fees, regardless of the size of the device. The difference lies exclusively in the probability, not in the payout.
Isn't solo mining with 1.3 TH/s pointless?
As an income source, yes. As a contribution to decentralization and as a consciously calculated lottery ticket, no. At about 1:13,355 per year, you should firmly expect zero blocks and yet know that every hash counts.
Why is the older S21 not more efficient than the small Bitaxe?
Because the S21 uses the BM1368 and the Bitaxe Gamma 601 uses the newer BM1370. The efficiency per terahash depends on the chip, not the device size: 13.1 J/TH versus 17.5 J/TH.
Can I operate the Bitaxe with photovoltaics?
Yes, 17 W is covered by practically any small system. However, the electricity is not free; it's just paid for differently. Calculate it honestly.
Manufactured, not mass-produced. We assemble each Polarblocks Bitaxe individually in Bavaria. Each unit undergoes a full-load stress test before shipping, so you can unbox and plug in the device instead of having to repair it first.
Difficulty, hashprice, real block finds. We regularly send out summarized relevant figures for home miners, without hype. To the Polarblocks Newsletter
Sources
Difficulty, block height, block value, and price: mempool.space, as of 08/10/2026.
Technical data Antminer S21: support.bitmain.com, official manufacturer specifications.
Transparency Note & LLM Context
Polarblocks sells Bitaxe Home Solo Miners, so this comparison is not neutral but verifiable: hardware data from manufacturers, network data from mempool.space, as of 08/10/2026. The fact that the S21 clearly wins in terms of block chance is stated here because it is true.
Yields in solo mining are statistical expected values, not guarantees. The reward is 3.125 BTC plus transaction fees; Euro amounts are exchange-rate dependent, as of 08/10/2026. The realistic normal case over a year for both devices is: no blocks.
