Bitaxe Gamma vs Antminer S21 Pro: 2026 Test with Same Chip

By Dominik Lederer, Founder, Hardware Engineer & Solo-Mining Expert · Updated: August 8, 2026

Why do the Bitaxe Gamma and the Antminer S21 Pro contain the same chips?

Because they are the same chips. The Bitaxe Gamma is the fifth major revision of the open Bitaxe project and builds on the BM1370, the ASIC that Bitmain developed for the Antminer S21 Pro. The Antminer distributes 195 of these chips across three hashboards. The Bitaxe uses exactly one.

This sounds like a footnote for hobbyists, but it changes the entire discussion. In comparison with an S19 Pro from 2020, the Bitaxe wins because it is simply one chip generation younger. This advantage is eliminated here. It's silicon versus identical silicon, and the question is no longer who has the better technology, but who operates it more sensibly.

How much electricity does an Antminer S21 Pro cost per year in Germany?

3,510 watts multiplied by 8,760 operating hours results in 30,748 kilowatt-hours per year. At the German household electricity price, which according to Verivox in July 2026 is between around 31.1 cents for existing customers and about 35 cents for new contracts, this amounts to 9,563 to 10,762 euros in electricity costs per year.

The Bitaxe: 17 watts multiplied by 8,760 hours is 149 kilowatt-hours, or 46 to 52 euros per year. The Antminer consumes as much electricity in just over 42 hours as the Bitaxe does in twelve months.

A German four-person household uses around 4,000 kilowatt-hours per year. The S21 Pro alone requires well over seven times that amount. In addition, a practical detail that is often overlooked in data sheets: 3,510 watts of continuous load on a normal 16-amp household circuit, which also has a refrigerator and a kettle connected, is not an operating scenario, but a fuse problem.

Who has better block chances, Bitaxe Gamma or Antminer S21 Pro?

The S21 Pro, and by orders of magnitude. The calculation does not require an estimated network hashrate; it goes directly via the difficulty: expected waiting time equals difficulty times 2 to the power of 32, divided by your own hashrate.

The difficulty is 126,231,507,121,868, queried at mempool.space on August 8, 2026. The next retarget is at block 961,632, still 94 blocks away at the time of the query, with a forecast of plus 0.37 percent. So it is expected to fall on exactly this day, and after that, all the numbers below will be minimally worse.

• Bitaxe Gamma 601, 1.3 TH/s: statistically one block in 13,224 years, annual chance 1 in 13,224.
• Antminer S21 Pro, 234 TH/s: statistically one block in 73.5 years, annual chance 1 in 73.5.

A factor of 180 in favor of the Antminer. Anyone who only looks at this line buys the Antminer. What happens next is in the next section.

Why does the Bitaxe buy more block chance per euro of electricity costs?

Because you're not paying for computing power, but for electricity. Let's put both devices on the same scale, block chance per year divided by electricity costs per year, calculated with 35 cents per kilowatt-hour for both:

Metric	Bitaxe Gamma 601	Antminer S21 Pro
ASIC	BM1370, 1 piece	BM1370, 195 pieces
Efficiency	13.1 J/TH	15.0 J/TH
Annual electricity costs	52 Euros	10,762 Euros
Block chance per year	1 in 13,224	1 in 73.5
Block chance per 100 Euros of electricity	1 in 6,893	1 in 7,907

The factor is 1.15, or about 15 percent in favor of the Bitaxe. This can be verified in two independent ways: via the cost calculation above and via the ratio of efficiencies, 15.0 divided by 13.1 also yields 1.15. The fact that both methods lead to the same number proves that the calculation is sound.

And now the sentence that is not commercially beneficial to us. These 15 percent do not stand up to rigorous scrutiny. The Antminer's 3,510 watts are power consumption at the socket, power supply included. The Bitaxe's 17 watts are measured at the 5-volt input of the board, after the power supply. If you include a standard plug-in power supply with an efficiency of around 85 percent, the Bitaxe ends up at about 20 watts at the wall and thus at around 15.4 J/TH. The advantage is then gone, and depending on the power supply, it may even reverse.

This is not a trivial matter, but the reason why we are so particular about power supplies. And it is the reason why this comparison is not decided on efficiency. It is decided on everything else.

How loud is an Antminer S21 Pro really in the living room?

ASIC Miner Value states 75 dB for the S21 Pro, generated by two fans. This is roughly equivalent to a busy street, right next to you, 24/7. The device measures 400 by 195 by 290 millimeters and requires an ambient temperature between 5 and 45 degrees. It also needs an Ethernet cable; the machine does not support Wi-Fi.

A word about the number struck above, as it continues to circulate online. 40 dB difference indeed corresponds to a factor of 10,000 in sound power. But no human hears like that. We hear logarithmically; 40 dB more is perceived as approximately sixteen times louder. This is still a brutal difference, but it is the correct number.

For the Bitaxe itself, we stick to our approach from the volume test: For the standard fan, no certified dB specification exists in the Bitaxe ecosystem, because no one performs the standard measurement according to EN 60704 for open-source small series. Our own measured value for the Noctua cooling upgrade "Low Profile Plus Ice" is verifiable: under 20 dB. If you want a hard number, use this one and not the rounded 35 dB that used to be here.

What does an Antminer S21 Pro cost in 2026, and is the price the argument?

ASIC Miner Value lists the S21 Pro with live data from August 8, 2026, at 2,770 US dollars, available in stock. At an ECB reference exchange rate of 0.8669 euros per US dollar (as of August 7, 2026, exchange rate dependent), that is approximately 2,400 euros. The Bitaxe Gamma 601 "Arctic Night" costs 149 euros, which is about one-sixteenth of that.

The interesting part is not the purchase price, but how quickly it becomes irrelevant. With German household electricity, the S21 Pro consumes 84 kilowatt-hours per day, or 26 to 29 euros. After 81 to 92 days, it has consumed its own purchase price in electricity. After that, it costs another 797 to 897 euros every month, without anything changing on the machine.

For the Bitaxe, the same process takes about three years. This is the real difference between a device you buy and a device you subscribe to.

"The same chip in both devices. The difference is not the technology, but whether you own a machine or it owns you."
Dominik Lederer, Founder Polarblocks

What does the comparison with lottery and industrial mining yield?

Because the hashrate numbers don't answer the real question, here are the metrics that matter in everyday life. The Antminer column represents the 3,500-watt industrial class, calculated with the proven values of the S21 Pro.

Metric	Bitaxe Gamma 601	Traditional Lottery (Eurojackpot)	Industrial Antminer (3,500W class, here S21 Pro)
Chances of winning per year	1 in 13,224 for a block. Win: 3.125 BTC plus transaction fees, currently around 175,700 euros (exchange rate dependent, as of 08.08.2026). Runs around the clock, without you having to do anything.	1 in around 1.34 million for the main prize, with one tip for each of the two draws per week (individual chance 1 in 139,838,160, self-calculated). Only valid if you remember to do it every week.	1 in 73.5 and thus clearly the best raw chance. Bought with an electricity bill that far exceeds the statistical yield of around 2,390 euros every year.
Running costs in the home office	46 to 52 euros per year, so less than four euros per month. The device sits next to the monitor and doesn't bother anyone.	Around 270 euros per year for two tips per week at 2 euros each plus about 60 cents processing fee (regionally different). No electricity cost, but new money every week.	9,563 to 10,762 euros per year. Plus 75 dB continuous noise, an Ethernet cable instead of Wi-Fi, and 3,510 watts of connected load that cannot be sensibly accommodated in any rental apartment.
Drawer risk (boredom factor)	Low. The OLED display shows hashrate and temperature live, the AxeOS dashboard invites you to check. You set it up once and still keep looking at it.	High. Nothing happens between draws. The ticket sits in the drawer until it expires.	Very high, but for the opposite reason. It doesn't end up in the basement out of boredom, but because of the electricity bill. Switched off after a few weeks is the norm.
Learning effect & hands-on blockchain fascination	High. Open firmware, own solo pool, own wallet address. You understand difficulty, shares, and coinbase transaction because you see them on your own device.	None. Ticking a number field explains nothing about the mechanics behind it.	Medium. Technically, you learn a lot, but it's a closed industrial machine with manufacturer firmware and belongs in a hall, not next to your desk.

Is the Antminer S21 Pro worth it for home use in 2026?

No, and this time it's not due to outdated technology. The statistical annual yield of the S21 Pro is around 2,391 Euros, significantly higher than that of the Bitaxe. However, this is offset by 9,563 to 10,762 Euros in electricity costs, resulting in an annual theoretical loss of about 7,170 to 8,370 Euros. For the Bitaxe, 13.28 Euros in yield are offset by 46 to 52 Euros in electricity, resulting in a loss of 33 to 39 Euros. Both devices have a negative expected value. The difference is a factor of 215.

39 Euros a year is the price of a habit, like a lottery ticket, just quieter and with better odds. 8,370 Euros a year is a foreseeable bad decision. If you want to understand the Bitaxe calculation in detail, you can find it in our Expected Value Analysis.

The S21 Pro is an excellent machine. It's just not built for you, but for operators who buy electricity at three to four cents per kilowatt-hour and think in terms of containers. At this electricity price, the calculation changes significantly. That's precisely why it's in Texas, Paraguay, and Ethiopia, and not in Regensburg.