What is an ASIC miner and how does it work
An ASIC miner is a computer built for just one task – calculating the hashes of one mining algorithm. ASIC stands for Application-Specific Integrated Circuit, i.e. an integrated circuit designed for a specific use. On its algorithm an ASIC is several orders of magnitude faster and more efficient than a CPU or a graphics card, but it cannot do anything else.
How an ASIC miner works
Mining Bitcoin means calculating the SHA-256 function over and over again, looking for a result that meets the network's target. We explain this in detail in the article What is cryptocurrency mining. A general-purpose processor uses only a fraction of its circuits for such a calculation. An ASIC chip has on its silicon only what the given algorithm needs, and hundreds of them work at once in a single machine.
Example: the Antminer S21 Pro+ delivers 245 TH/s, i.e. 245 trillion attempts per second, at a power draw of 3,675 W. It therefore needs 15 J per 1 TH/s – we discuss this efficiency unit in the article ASIC miner power consumption and J/TH.
What an ASIC miner consists of
| Component | What it does |
|---|---|
| Hashboards | They carry the ASIC chips and do the actual mining. The Antminer S21 has 3 boards with 108 chips each. |
| Control board | A small computer with Linux and firmware. It distributes work to the chips, communicates with the pool and provides the web interface. |
| Power supply (PSU) | Converts AC mains voltage into low DC voltage for the hashboards. |
| Cooling | Fans with heatsinks; on more powerful models a water block (Hydro) or submersion in liquid (immersion). |
| Temperature sensors | They monitor the temperature of the boards and chips; the firmware uses them to control the fans and performance. |
| RJ45 network port | Wired internet connection. Large miners have no Wi-Fi. |
ASIC or graphics card?
| Feature | ASIC miner | Graphics card (GPU) |
|---|---|---|
| Algorithms | one, hard-wired in the chip | many, depending on the software |
| Performance on its algorithm | the highest | several orders of magnitude lower |
| Other uses | none | gaming, graphics, AI |
| Noise | around 75 dB for large machines, 40–55 dB for home models | significantly lower |
| Risk | it becomes obsolete or its algorithm disappears | can be sold outside mining too |
Bitcoin, Litecoin, Dogecoin, Kaspa or Zcash are today practically mined only by ASIC miners. Graphics cards make sense for coins for which no ASIC exists – see Which cards are suitable for mining. ASIC-type chips can otherwise also be found in phones, network equipment or cars, but there they solve completely different tasks.
Why it matters for miners
An ASIC is tied to an algorithm, not to a coin. A SHA-256 miner mines Bitcoin, Bitcoin Cash and other coins with the same algorithm, but never Kaspa. Before you buy a machine, check which coins run on its algorithm:
| Algorithm | Coins | Typical machines |
|---|---|---|
| SHA-256 | Bitcoin, Bitcoin Cash, eCash | Antminer S21, S23, Fluminer T3, Avalon Q |
| Scrypt | Litecoin + Dogecoin (mined simultaneously) | Antminer L9, ElphaPex DG1+, Fluminer L1 Pro |
| kHeavyHash | Kaspa | IceRiver KS7 |
| Equihash | Zcash | Antminer Z15 Pro |
| Blake2b-Sia | BTCB2, Siacoin | iBeLink BM-S3+, Goldshell SC6 SE |
The second risk is obsolescence. Each new generation needs less energy for the same hashrate, so older machines gradually stop earning. The extreme case came in 2022, when Ethereum moved to Proof of Stake and miners for its algorithm lost their main coin (see Ethereum and Proof of Stake).
Related terms
- Hashboard – the board of chips that does the mining in a miner.
- ASIC miner manufacturers – Bitmain, MicroBT, Canaan and smaller specialists.
- ASIC miner lifespan – how long a machine lasts and when it stops paying off.
What next
If you are choosing your first machine, go through the guide How to choose the right ASIC. Current models by algorithm can be found in the ASIC miners category.
Sources
Frequently asked questions
Can I use an ASIC miner for a different cryptocurrency?
Can an ASIC miner be used as an ordinary computer or for AI?
Why is an ASIC miner so noisy?
How much electricity does an ASIC miner use?
Why isn't Bitcoin mined on graphics cards?
This text was prepared with the help of AI. Facts, figures and procedures were checked by Yegor.
