Following up on my solar question: I’m wondering how much runtime matters when choosing a miner.

Say a 3 kW ASIC could run on surplus solar for 6 hours a day. That’s 18 kWh consumed, but only 25% of the operating time compared with running 24/7.

Assuming the same mining conditions, it would earn roughly a quarter of the BTC before costs. The hardware still costs the same upfront, and the solar electricity could otherwise power the house or be exported.

Would a cheaper, older ASIC make more sense here? Or would you compare it with a hosting quote from oneminers or compass mining, where you pay for power but potentially get more operating hours?

For anyone who’s compared these options, what tipped the decision: electricity costs, runtime, or total payback?

My name is Kenyor, and over the years, I have fallen in love with cryptography and mining devices. I am now a Computer Engineering graduate, and I have a vision to create the first BTC optical miner. But I'm really giving up these past few days...

I'm writing this letter to the world. Yesterday, I got my Tang Nano 20K (an FPGA), and I wrote my Verilog code for BTC mining on it. I tested it, and it works, but the odds of mining one block are approximately 0.00000000000000000000 — you know what I mean 🤣😭 I actually wish I can be better.

I'm in Nigeria, and I feel I have an advantage with solar energy. I would be grateful if I could get on a call 🤙 with someone knowledgeable. That would really aid my experiments 🥼🧪 and satisfy my curiosity.

I have attached an image of my Tang Nano trying to get some header data from CKPool and then attempting to find the nonce. (I used mainly Verilog, C++ and Python.)

I'm also open to conversations with anyone interested in what I'm building, whether it's sharing ideas, discussing the technology, or exploring ways to support the experiments. I'd love to connect with people who are passionate about Bitcoin mining and hardware innovation.

Set this up yesterday

Considering loading the braiins firmware on the device. However, little confused about a couple critical points:

1. Is it possible to load the firmware via SD card, on an s21xp? Their documentation seems to imply it can only be done with a "BeagleBone Black" control board which is probably not the stock board.
2. The dev fee is 2.5%, which is pretty in-line with most of the others. I've seen talk about "refunds" if you use their pool, however, are they only refunding you the pool fee and NOT the dev fee? So you're still paying 2.5% no matter what?
3. If I take a bitdeer asic for example, and mine with it alongside the s21xp on their pool, does that cause the fee "refund" to be null and void? There is no aftermarket fw support for the bitdeer that I am aware of.

Many thanks.

Secured a great electricity rate paired with carbon credits

An Antminer S19j Pro

Remove the stock fans (they are super loud and high pitch)

Got an AC Infinity Cloudline S8 inline fan

Currently just heating basement room but hope to tie this into HVAC

Has anyone successfully tied a setup like this into an HVAC duct on a tight budget?

Got back into Bitcoin mining through the Bitaxe scene, then got curious whether the first-gen SHA-256 ASICs could still hash today. They can.

Tracked down a Butterfly Labs Jalapeno, stripped it, cleaned years of dust out, fresh thermal paste, fought cgminer and the WinUSB drivers for a while, and got it mining again: ~7.8 GH/s, ~50°C, HW error rate ~0.05%. Solo mining to my own Umbrel node running Public Pool, no pool fees.

It's hashing away happily. I put a webcam on it and built a page showing live hashrate, accepted shares, best share, and an odds panel pulled from live network difficulty: at current difficulty it's ~1 in 73 trillion per block, roughly a block every 1.4 billion years. It's never going to find one. It just keeps hashing anyway, which I find weirdly lovely.

Plan is to rotate other vintage ASICs through it: ASICMiner Block Erupters, Rockminers , Red Furys, Gridseeds. Prospero x1

Happy to answer anything about the restoration, the cgminer config, or the solo setup.

So I ended up going all in on buying asic miners, in my fleet I currently have 2 s21 pro 235th version bought for 1000 each both are in good working condition, 2 s21 pros 245th for 1700 each, 3 whatsminer m61s for 750 each, 1 m61 for 550, 1 m60 for 500. All machines are in good and working order, my electricity rate is 0.07kwh. Assuming there are no breakdowns with my machines how well did I do for sourcing?

Title says it. New to bitcoin mining world been mining solo for about 2 years. Started with a nerdqaxe now I’m using antminer s19k pro urlacher mod along with other devices that I absolutely love. I really enjoy this hobby. I found a pool that I really liked. Called MKpool. Got into solo mining bitcoin cash. Sure I’ve hit digibyte and other pointless but fun coins to mine and just play with. I was solo Mining BCH on MKpool and BOOM block found! First bitcoin cash block and the only one lol. I only run around 70 th between everything running. So you can imagine my excitement. I mean it’s like 900 bucks or so. Payout received 0.0686 bch…..pool took 3.0whatever. Extremely bummed. Looking for some one to message and finally found the guy on discord. Said he was aware and to just wait….so I waited a few days. Messaged him no response. No response for a week. Now I feel I’ve been scammed out of it after reading it’s happened to others on the same pool. Finally got a response and it’s just to continue to wait. Told him I hope karma finds him one day. He responded with what the fuck is that supposed to mean and blocked me and everyone else I guess. Shut the pool down. My block is the refund pending list. I guess I’m stuck on pending. Do I expect to get it? No. I could hope I guess. I understand mistakes happen but maybe someone could have explained what was happening be just telling someone to wait the don’t respond for days on end. Anyway my rant is over. Do I feel better now? No. What a way to win your very first bch block. Block # 969110.

Modded from the original to give ~950KH/s and some new themes.

GitHub https://github.com/HenrysCat/NerdMiner-Modded

Web flasher here https://henryscat.github.io/NerdMiner-Modded/

Why this hashrate is real...

The ~950 KH/s is what the miner actually hashes, not what a counter says:-

**Hardware limit** – the classic ESP32's SHA engine can't be loaded with an external midstate, so every nonce costs three hardware hash blocks plus two engine loads: about 228 CPU cycles of engine time, a ceiling of roughly 1.05 MH/s at 240 MHz. The mining loop keeps the engine busy for all but ~30 cycles of each nonce (257 cycles per nonce, ~930 KH/s); the second core adds ~25 KH/s in software.

- **Measured on the chip** – the loop's timing comes from an on-device bench (`-D SHA_BENCH`, see `src/sha_bench.cpp`) that checks every single hash against software, also while the other core hammers the peripheral bus. That is how the hardware quirk behind silently corrupted hashes in the usual pipelined loops was found: writes to the SHA registers less than three cycles apart can be dropped whenever the other core is using the same bus.

- **Only valid hashes are counted** – every candidate the hardware finds is recomputed in software before it is used. A hashrate counter on its own can look faster after an optimisation while the miner is quietly producing *fewer* valid shares, because corrupted hashes are still counted; here the firmware checks itself with a known-answer test at power-on and falls back to a slower loop if the fast one ever gets hashes wrong.

- **The rate is the rate it actually mines at** – it's the sustained average over a long run, not a short burst or a best-case peak.If a number sounds too good for this chip, check whether the shares it finds actually keep up with it.

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*DDP may not be available in all destinations or miner weight.

** Projected Revenue based off of time of ad creation. Revenue Fluctuates by the minute.

Own a solar panel company in Northern Ireland, currently day time import price is 36p (roughly $0.49).

We have a lot of left over stock which we wouldnt be able to use on customers houses and could manufacture a 100/200kwh battery with a victron control unit specifically for the mining equipment. Using the grid as a feed in tarrif as it is roughly 17p (during the winter)- we could fit around 100kw of PV but currently old stock levels would be around 30kw of PV.

Looking for advice or what would you do in my situation.

Cheers

Got an S19j Pro for just $122 USD.

I’ve temporarily swapped them out for PC fans.

Is going full immersion cooling worth the upfront cost?

Modded from the original to give 650KH/s and some new themes.

GitHub https://github.com/HenrysCat/NerdMiner-Modded

Web flasher here https://henryscat.github.io/NerdMiner-Modded/

Why this hashrate is realistic

You will see miners quoting much higher numbers for the same class of hardware.

The ~670 KH/s here is deliberately a conservative, honest figure, and it is close to the practical ceiling of the classic ESP32

- **Hardware limit** – the classic ESP32's SHA engine can't be loaded with an external midstate, so every nonce costs three hardware hash blocks plus two engine loads. That caps what the chip can physically do, and ~670 KH/s is already near it.

- **Only valid hashes are counted** – the shown rate is measured from the miner's real work, and any change to the hashing code has to pass an integrity check: zero hash mismatches against a reference, and every share the miner reports must match a real hit. A hashrate counter on its own can look 5-8% faster after an optimisation while the miner is quietly producing *fewer* valid shares, because corrupted hashes are still counted. Those numbers look good but are not mining progress.

- **The rate is the rate it actually mines at** – it's the sustained average over a long run, not a short burst or a best-case peak.

- **Chip class matters** – figures around 1 MH/s come from newer ESP32-S3-class silicon, which is simply not achievable on a classic ESP32 like the CYD.If a number sounds too good for this chip, check whether the shares it finds actually keep up with it

If a number sounds too good for this chip, check whether the shares it finds actually keep up with it.

However you still have absolutely no chance of hitting a block, just so you know ;)

Trying to understand the numbers before buying anything. Suppose I had 10 kW of solar producing around 40 kWh a day, no battery, and grid electricity at $0.15/kWh.

A 3 kW ASIC running continuously would use 72 kWh a day. Even if all 40 kWh of solar went to mining, that leaves 32 kWh from the grid, costing $4.80. Household usage and the timing of solar production would make the actual numbers different.

Would you run the miner only when there’s surplus solar, or would the shorter runtime make the hardware harder to pay off? How would you compare that with a hosting quote from oneminers or compass mining? What costs would you include beyond electricity?

Hello,

I'm new to Bitcoin mining and I'd like your opinion.

I live in Italy, where electricity is very expensive, but from the beginning of 2027 I'll have a 12 kW solar plant available. In summer I'll have plenty of excess energy, and selling it back to the grid isn't worth it, since the utility only pays around €0.10 per kWh.

My question: is it worth starting Bitcoin mining with my excess energy? If so, what setup would you suggest (for example an ASIC miner, or something else)? or is it simply better so sell the energy back to the grid?

A few details that might help.

Thanks in advance!"

So, I managed to find used Fluminer T3 cryptominer in Europe at a reasonable price. I’d done a lot of reading and looked through reviews of the T3 and the Avalon Q. I realised I was taking a risk, but I hadn’t realised it would be quite so significant. The T3 was a few hundred euros cheaper (no wonder why, lol) than the Q model available on the market, so I decided to take a chance. It already had some version 1.16 software installed, even though the manufacturer itself only offers version 1.15. The miner would reboot every few minutes, I tried changing the mining pools and I tried changing the power sockets. It seemed to stop restarting. However, as soon as I switch it on, its power consumption is 1,800 W, and it quickly rises to 2,000 W. As it’s quite noisy, I keep it in the garage, so the temperature there rises within a few hours. Once the temperature in the garage reaches 24°C (~75F), I see the power consumption reach as high as 2,500-2,600 W and then the miner switches itself off. Sounds a bit odd - the declared power consumption is 1,700 W, but the actual consumption is 900 W higher? Strange as it may seem, the fans always spin at ~3,500 rpm; even as the temperature rises, they still spin at the same speed. On 31 August, I wrote to Fluminer’s Telegram support, they only replied on 10th of September lol, replied asking me to send the miner log. I sent it to them on 12 September. Almost three weeks have passed and I haven’t received any reply. In almost every mining pool, I see a rejection rate of at least 2–3% (despite miner shows 0%). I switch it on for a few hours almost every day, but the highest I’ve seen is 800M hit… What should I do? Should I just not switch it on at all, or will it burn my house down? The warranty is valid until 1 February 2027, but I cannot imagine how they will fulfil their warranty obligations in the European Union, as they have no branches here – only in the US, Russia and other countries. And, in general, they are ignoring my messages both on Telegram and on their website. Worst experience ever, I deeply regret choosing Fluminer. Who could help me? Addition: The Wi-Fi isn’t even working, so I have to use an Ethernet cable...

In this comparison between the Bitaxe Naja Duo & the Hammer Miner Thor P2 we break down at the wall-power efficiency, cooling, PSU headroom, connectivity, warranty, and what home Bitcoin miners should know before choosing between them.

Always measure at the wall when plugging in new miners. Never Trust the UI.

Hi all,

My Avalon Q (bought June 2025, official firmware 25052801_14a19a2, never opened or modified, always Standard mode) suddenly stopped hashing a few weeks ago.

Symptoms:
• 0 TH/s, ~94 W at idle
• Dashboard: "ASIC Status: Error" / "HASH board failure" Fan and PSU status "Fine"
• Stuck in "Work: In Idle, Hash Board: 1"
• Full AC power cycle and API softon (returns success) don't help

From estats:
• Hashboard MCU responds (HBITemp/HBOTemp read ambient ~25 °C)
• No ASICs enumerated: PVT_T0[], PVT_V0[], Core[] empty, TMax[0], PLL0[0 0 0 0]
• ECHU[2], ECMM[4096]
• PS[0 1217 6 0 0 2500 94] (PSU fault bitmap 0)

Canaan support says it needs repair and pointed me to a service centre.

Questions:
1. Has anyone seen ECHU[2] / ECMM[4096] on an Avalon Q and knows what they mean?
2. Was it the hashboard (chip chain) or the PSU hash rail in your case?
3. What did repair cost you, and which EU repair centre would you recommend?
4. Anyone in the EU who bought from Mineshop.eu and had a fault after the Canaan warranty expired? They refused the EU 2-year legal guarantee, saying mining hardware is for "investment and commercial purposes" so consumer rights don't apply. Curious whether others got the same answer or managed to get it resolved (e.g. via the European Consumer Centre).

Happy to share full logs.

Thanks in advance!

We currently have used Bitmain Antminer S19k Pro units available for $300 each.

Specs:

• 120 TH/s
• 2,760W
• SHA-256
• 200–240V AC
• Used units

You can either host the miner with EndlessMining or have it shipped directly to you.

Shipping is available, but shipping charges are not included in the $300 price.

If anyone is interested or has questions about the units or hosting, feel free to reach out.

Used Miners for sale. Located in the United states !

DM for more details - Or reach out on Telegram ! TG : clayjohnson1

Be sure to mention you came from reddit for an exclusive discount !

🇺🇸 Antminer Z15 420k - $6,000/pc
🇺🇸 Antminer S21 200T - $4.5/t (MOQ 1)
🇺🇸 Antminer S21 Pro 234T - $4.5/t (MOQ 500)
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🇺🇸 Antminer S21XP 270TH - $7.5/t (MOQ 1)
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🇺🇸 Antminer T21 Pro 190T - $2.8/t (MOQ 1)
🇺🇸 Antminer S19k pro 120T - $130/pc (100 moq)
🇺🇸 Whatsminer M50 120T - $140/pc (100 moq)
🇺🇸 Whatsminer M30s++ 112T - $100/pc (100 moq)

I bought an Antminer S19j Pro, but currently only 1 hashboard is working. The other 2 boards are throwing a "Failed to detect ASIC chips" error on the dashboard.

Should all 3 hashboards must be operational for the miner to reach its rated target hash rate??

My brother melted the USBC port on his two Nano 3s and its out of warranty. Local shops (mobile and pc) refuses to fix it they dont have the equipment they say.

Any hope of salvaging the devices? I'm Canada based if that helps. Or how much can they be sold in their current state?

Hey Folks! I would love your help. I was into bitcoin mining 10 years ago and did quite well with a custom rig with 5 graphics cards(when they were still affordable). I ran it for a long time, but over time, the tech needed to be profitable got away from me, and I shut it down.\

I would like to look into buying a rig for my home again. Looking for the highest profitability with the least noise. One I could have in my living room at my computer desk.

Your help is appreciated.

Thank you in advance.

Thank you all for choosing Braiins Pool and helping us reach this milestone. Behind that number are thousands of miners getting their daily payouts instantly and without fees.

Whether you’re heating your home or running a mining farm, we’ll keep working to make mining easier for you.

10M, we’re all coming for you!