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Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Clear out junk files and repair common Windows errorsFree Scan →The Bitmain Antminer KS3 is a dedicated Kaspa (KAS) ASIC miner that uses the KHeavyHash algorithm. Bitmain’s listed KS3-9.4T model is rated at 9.4 TH/s and 3,500 W at the wall under its stated test conditions—about 84 kWh a day at rated power. It needs 200–240 V AC, substantial ventilation and a plan for heat and fan noise. Those requirements, plus volatile KAS mining economics, make the KS3 a specialized purchase rather than a plug-in household appliance. Verify the exact unit and recalculate costs before buying; a model name or seller’s profit estimate is not enough.
What the Bitmain Antminer KS3 does
The KS3 is a Bitmain ANTMINER built to calculate hashes for Kaspa using KHeavyHash. It is an ASIC: its chips are designed for that workload, not general-purpose computing. Software cannot turn it into a Bitcoin or Litecoin miner, or into a general-purpose Ethereum miner. Nor is “KS3” interchangeable with similarly named Kaspa miners from IceRiver or other manufacturers; those are different products.
Keep three identifiers distinct when assessing a listing: the manufacturer’s model designation, the hashrate the seller advertises, and the unit’s measured performance. Bitmain’s published specification is for the KS3-9.4T. A used machine’s actual output depends on its hardware condition, configuration and operating environment.
Official KS3-9.4T specifications
| Specification | Bitmain listing |
|---|---|
| Model/version | KS3-9.4T / KS1-10 |
| Algorithm and intended coin | KHeavyHash; Kaspa (KAS) |
| Hashrate | 9.4 TH/s |
| Power at wall, at 25°C | 3,500 W ±10% |
| Efficiency | 0.37 J/Ksol ±10% |
| AC input and frequency | 200–240 V AC; 47–63 Hz |
| Rated current | 20 A |
| Network | RJ45 Ethernet, 10/100M |
| Dimensions, unpackaged | 430 × 195.5 × 290 mm |
| Dimensions, packaged | 570 × 316 × 430 mm |
| Weight, net / gross | 15.2 kg / 16.9 kg |
| Operating temperature | 0–40°C |
| Storage temperature | −20–70°C |
| Operating humidity | 10–90%, non-condensing |
| Maximum operating altitude | 2,000 m, subject to temperature derating |
These figures are Bitmain’s published specifications, not independent test results. The 3,500 W figure is stated at the wall at 25°C with a ±10% tolerance. Dividing 3,500 W by 9,400 GH/s gives about 0.372 J/GH; this is a calculation from the listed figures, not a separate efficiency measurement. Bitmain expresses its efficiency as J/Ksol, while third-party listings may use J/GH.
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- BITMAIN Antminer S21 XP 270T 3645W 13.5J/T BTC/BCH/BSV Bitcoin SHA256 220~277V Air-cooling Miner.
- The Hashrate value, Power on wall, and Power efficiency on wall are all typical values, The actual Hashrate value fluctuates by ±3%, and the actual Power on wall and Power efficiency on wall fluctuate by ±5%.
- Caution: Wrong input voltage may probably cause server damaged. Power supply AC input voltage, 220~277 Volt.
- When the server is used at an altitude from 900m to 2000m, the highest operating temperature decreases by 1℃ for every increase of 300m.
Bitmain says the 20 A current rating is based on two AC input wires at 10 A each. It warns that incorrect input voltage can damage the server. Above 900 m elevation and up to 2,000 m, the maximum operating temperature decreases by 1°C for every additional 300 m. Check the complete Bitmain KS3 specification for the unit and installation conditions.
KS3 variants: confirm what is actually for sale
Listings use “KS3” for more than one hashrate configuration. Bitmain’s specification covers a 9.4 TH/s model; a third-party listing describes an 8.3 TH/s unit drawing about 3,188 W. That listing-specific figure does not establish the power draw of every 8.3 TH/s machine or every KS3. Do not apply the official 9.4 TH/s figures to a different unit without verification.
Before paying, ask the seller for:
- The exact model and advertised hashrate version, plus the serial number.
- A dashboard screenshot showing current and average hashrate, detected hashboards, temperatures, fan speeds and firmware version.
- The wall-power reading and how it was measured.
- A video showing the specific unit running and hashing, if buying used.
- Repair history, proof of purchase, warranty status, return terms and shipping origin.
- Confirmation that the original power supply is included, if the sale claims it is.
A listing title or a brief startup reading cannot establish sustained performance. Compare time-based hashrate averages, not just a momentary number. The ASIC Miner Value 8.3 TH/s KS3 listing is useful as an example of a separately listed variant, not as a universal specification.
Power, electrical installation, heat and noise
Estimate the electricity load
At Bitmain’s 3.5 kW rated wall draw, continuous operation uses about 84 kWh per day and 2,520 kWh over 30 days. The following power-only costs use those calculations; they exclude pool fees, cooling, hosting, taxes, demand charges, downtime and purchase recovery.
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| Electricity rate | Approx. daily power cost | Approx. 30-day power cost |
|---|---|---|
| $0.05/kWh | $4.20 | $126 |
| $0.07/kWh | $5.88 | $176.40 |
| $0.10/kWh | $8.40 | $252 |
| $0.12/kWh | $10.08 | $302.40 |
| $0.15/kWh | $12.60 | $378 |
| $0.20/kWh | $16.80 | $504 |
For your own rate, use: daily power cost = 3.5 kW × 24 × electricity rate per kWh. The KS3 specification gives a wall-power figure, so do not add an assumed power-supply loss on top of it; account separately for any additional cooling equipment or facility costs.
Rank #2
- This is Brand New Antminer s21 200T 3500w, power consumption is only 17.5w/T, can save much eletric cost
- As Bitcoin Miner price are change with the btc, we will charge 40% restock fee if customer return within 30 days
- Bitmain Antminer s21 200T is the most powerful miner for customer who want Bitcoin Miner, much better than Antminer s19xp 141t, Antminer s19kpro 120T, Antminer S19jpro 120t and whatsminer m60s
- According to Bitmain, Antminer s21 works best to 200t 17.5j/t when ambient temperature around 0-40 degree, if above 40 degree, may reduce to 180t 18.5j/t , please be aware of your temperature
- As Bitmain Antminer s21 200T is first batch, will need 220-277V voltage, so please do not use 110V voltage, it may make the miner defective, include power cords
Plan a suitable circuit
The KS3 requires 200–240 V AC, not a standard 120 V household circuit. A 3.5 kW continuous load warrants a properly designed installation. Have a qualified electrician select the circuit, receptacle, breaker, wire gauge and PDU, and confirm load balancing, circuit headroom and compliance with local electrical and utility rules. Do not use improvised adapters, damaged connectors or undersized extension cords, and do not assume a shared circuit is suitable.
Allow for heat and airflow
Nearly all electricity consumed by the miner becomes heat. At the rated draw, it is roughly a 3.5 kW continuous heat source before any separate cooling equipment is counted. Intake and exhaust need a clear path, with hot exhaust kept from recirculating into the intake. Dust, lint, insects and moisture can threaten reliability. In a warm climate, ventilation or air conditioning can materially increase the operating cost.
Bitmain’s published specification does not establish a universal sound-pressure figure. Fan noise can nevertheless make ordinary living spaces unsuitable. Home operation is technically possible with appropriate power and airflow, but noise, heat, electrical work and utility rates often make it impractical. A garage or basement still needs suitable ventilation, dust control, moisture management and fire-safety planning.
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How to set up a KS3 with a Kaspa pool
Pool addresses, ports and interface labels can change, so use the current instructions from the pool you select and the manual for your miner’s firmware. Have a Kaspa wallet address, Ethernet connection, router or DHCP server, pool stratum address and port, and a worker name if the pool requires one. Do not treat a pool as “official” unless Kaspa documentation establishes that status; the Kaspa Wiki hashrate tables provide reference information, not an endorsement of a particular pool.
- Choose a dry, ventilated location with unobstructed intake and exhaust. Confirm the electrical installation is ready before applying power.
- Connect Ethernet to the miner and your network, then connect the AC power using the correct arrangement for the unit.
- Power on and allow the miner to boot. Find its address in the router’s DHCP client list or with a Bitmain-supported network-discovery method.
- From a device on the same network, open the miner’s web interface. Change the default administrator password immediately.
- Enter the pool’s current Kaspa stratum URL and port, plus your wallet address and worker identifier in the relevant fields. Save and apply the configuration.
- Check that the miner detects its hashboards and fans, and confirm the worker appears at the pool. Watch accepted shares, local and pool-side average hashrate, temperatures, fan speeds, rejected shares and alarms.
- Record the firmware version and configuration details securely so you can restore a working setup if needed.
A pool’s displayed hashrate can lag or differ from the local dashboard because it is averaged over time. An “online” worker is not proof of efficient mining: check accepted shares and sustained hashrate as well.
Rank #3
- This is Brand New Antminer s21 200T 3500w, power consumption is only 17.5w/T, can save much eletric cost
- As Bitcoin Miner price are change with the btc, we will charge 40% restock fee if customer return within 30 days
- Bitmain Antminer s21 200T is the most powerful miner for customer who want Bitcoin Miner, much better than Antminer s19xp 141t, Antminer s19kpro 120T, Antminer S19jpro 120t and whatsminer m60s
- According to Bitmain, Antminer s21 works best to 200t 17.5j/t when ambient temperature around 0-40 degree, if above 40 degree, may reduce to 180t 18.5j/t , please be aware of your temperature
- As Bitmain Antminer s21 200T is first batch, will need 220-277V voltage, so please do not use 110V voltage, it may make the miner defective, include power cords
Firmware and access security
Download firmware through Bitmain’s official process by selecting the algorithm, model and firmware version on the Bitmain firmware download page; its firmware instructions explain the supported path. The KS3 manual gives an example firmware version, 20230920, and describes a version-dependent “System → Firmware Upgrade” path. It warns that power must not be interrupted during an upgrade; an interrupted update can require return to Bitmain for repair. Consult the manual and interface for your firmware version rather than assuming the older labels remain current.
Bitmain says KS3 series Secure Boot is enabled and Root Authority is disabled. Older Antminer rooting or custom-firmware instructions may therefore not apply. Keep the management interface off the public internet, avoid router port forwarding to it, and use a private LAN or VPN. Use a separate mining wallet address if appropriate; never enter a wallet private key into a miner interface or pool.
How to judge KS3 profitability
Start with net cash flow, not a headline earning figure
Use this structure:
Daily net operating result = mining revenue − electricity − pool fees − hosting − cooling − maintenance reserve − other operating costs.
Then assess whether the remaining cash flow can justify the delivered machine cost, installation, taxes and risk. A positive daily operating result alone does not mean the purchase will recover its cost.
At the 9.4 TH/s model’s listed 3,500 W, power alone costs about $8.40 a day at $0.10/kWh. Revenue must exceed that amount before pool fees, cooling, downtime and other costs just to cover electricity. This is a break-even threshold calculated from Bitmain’s power specification, not a revenue forecast.
Rank #4
- This is First Batch Released Antminer S21 200th Bitcoin Miner include psu , Bitmain Antminer S21 200th asic crypto miner is ready for you do mining
- We Will charge 40% restock fee if return the antminer s21 200th/s within 30 days, so please make a serious consideration before purchase
- Bitmain Antminer S21 200t is in stock now, we cover custom tax for customer
- Please kindly note that the required input voltage for Bitmain Antminer S21 is 220V-277V. Wrong input voltage may probably cause miner damaged
Use current inputs and test scenarios
A live estimate needs the exact unit’s hashrate and wall power, current KAS price, network hashrate or difficulty, block reward or emission rate, pool fee, expected uptime and your actual electricity rate. Include delivered purchase cost, shipping, customs, taxes, electrical installation, hosting or cooling, repairs and a realistic resale assumption. Mined KAS per unit of hashrate can decline as network hashrate grows; a calculation holding today’s network conditions constant is not a long-term promise.
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1Fix the driver behind crashes, sound loss and screen glitches2Clear out junk files and repair common Windows errors3Scan for outdated or missing drivers - takes under a minuteUse bear, base and bull cases that change KAS price and network conditions, and a separate hardware-loss or repair case. For each, compare operating costs and the period over which the machine could run; do not present a fixed payback period as assured. Bitmain’s mining profit calculator accepts inputs such as hashrate, power, electricity rate, miner price, quantity and other daily costs. Bitmain describes its output as a reference estimate based on current network difficulty, not a guarantee.
One dated example shows why snapshots cannot be generalized: ASIC Miner Value’s 8.3 TH/s KS3 page marked an estimate of about −$7.65 per day at $0.10/kWh as updated July 26, 2026. That was a third-party estimate for the listed 8.3 TH/s variant, not a result for every KS3 or a current forecast.
Compare alternatives on equal terms
Mining is a choice among using capital for a KS3, a newer Kaspa ASIC, hosting or renting hashpower, buying KAS directly, or keeping the money available. Compare total delivered costs and risks, not gross mining revenue against zero. Hosting quotes should be checked for cooling inclusion, setup and maintenance fees, revenue share, contract length, termination rights, insurance, downtime policy, repair responsibility, shipping risk and withdrawal terms.
Bitmain’s KAS shop category is at shop.bitmain.com/?coin=KAS. The commercial snapshot dated August 16, 2026 did not show a KS3 retail listing in the returned material, so it does not establish current new-machine availability. Bitmain support lists newer KAS products, including KS5 and KS5 Pro, but available information here is insufficient for a responsible numerical comparison. Check current official specifications and pricing before comparing efficiency or value.
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- 【Hashing Power Prowess】 Delivers a powerful hashrate of 96TH/s ±3%, efficiently mining SHA256 algorithm cryptocurrencies like BTC, BCH, and BSV.
- 【Optimized Power Consumption】 Consumes approximately 3250W ±5%, with a power efficiency of 33.9J/TH ±5%, ensuring a balance between performance and energy usage.
- 【Versatile Power Supply】 Supports AC input voltage from 200-240V and frequency range of 47-63Hz, compatible with diverse mining setups worldwide.
- 【Adaptable to Mining Environments】 Operates reliably in temperatures ranging from 32°F to 113°F (0°C to 45°C), with non-condensing humidity between 10-90% and altitude up to 2000 meters.
- 【Refurbished but Fully Functional】 This is a refurbished unit that works well, but may have minor surface scratches due to previous use. These cosmetic imperfections do not affect the miner's performance. ※IMPORTANT※ This is a refurbished aluminum plate model without official BITMAIN warranty. The power cord is NOT INCLUDED. Please use 220-240V input voltage only to avoid potential damage. Returns without malfunction incur a 40% restocking fee.
Buying a used KS3: verification checklist
The official KAS shop result did not show a current KS3 retail listing in the August 16, 2026 snapshot. That leaves buyers likely to encounter used, refurbished, broker-held or third-party inventory; it does not establish that every such listing is used. Before payment, get the exact variant, serial number, dashboard and operating evidence in writing, along with the seller’s return and shipping terms.
Before sending money
- Match the serial number and model to the machine and request proof of purchase.
- Review a dashboard screenshot for sustained average hashrate, hashboard count, temperatures, fan speeds and firmware version.
- Ask for the power reading, test conditions and a video of the specific miner hashing.
- Request repair history and warranty status, and verify the serial through Bitmain where possible.
- Confirm whether the PSU is included and original, who pays shipping and customs, and who bears transit risk.
- Get a written return policy and distinguish a seller’s warranty from Bitmain coverage.
Inspect on arrival
- Look for damaged packaging, bent chassis, corrosion, moisture, missing screws or fan guards, dust contamination, burn marks and melted connectors.
- Check whether the control board appears non-original and whether all hashboards initialize.
- Listen for abnormal fan noise; review dashboard warnings, hashrate stability and rejected shares while the unit runs.
- Document errors and contact the seller or service provider before opening or modifying the miner.
Bitmain’s support center covers support topics including repair, fraud, parts and manuals. Use official Bitmain domains for firmware, warranty checks and support rather than downloads sent by an unknown seller.
Warranty, repairs and maintenance
Do not assume a universal warranty duration for a KS3. Bitmain’s product warranty page says new BTC miners and new power supplies are generally covered for 365 days subject to the sales contract, while its miner warranty-check page gives a general 180-day rule for new miners other than 19-series models. Those statements do not settle coverage for a particular KS3. The sales contract and serial-number result matter; used coverage may not transfer, and the seller’s promise is not the same as Bitmain’s warranty.
Confirm coverage and repair arrangements before purchase. Bitmain’s parts-purchase process describes a separate process, and parts availability is subject to stock; parts access does not guarantee repairability or warranty coverage. Opening or modifying a unit may affect warranty eligibility.
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KS3 troubleshooting by symptom
The miner does not power on
- Have a qualified person confirm the correct 200–240 V supply, both AC input connections, breaker, PDU and power cables.
- Check for a tripped circuit, voltage drop, PSU problem or overheated or damaged connector.
- Note whether the control board shows any LEDs. Do not keep cycling power through a damaged or overheated unit.
The miner powers on but hashrate is zero
- Check Ethernet link, miner IP address and access to the web interface.
- Confirm the pool URL and port, wallet and worker syntax, and whether DNS or firewall rules block the connection.
- Check whether all hashboards are detected and whether fan or temperature alarms appear.
- Compare local status with pool-side worker status and review firmware compatibility.
A hashboard is missing
Possible causes include a loose or damaged data cable, a power-connector issue, a hashboard or control-board fault, overheating, or a firmware or initialization problem. Record logs and error codes before disassembly, then use the applicable support or repair channel.
Hashrate is below the advertised figure
Check the exact model first. Other possibilities include normal specification tolerance, high temperature or poor airflow, a missing or faulty hashboard, pool averaging delay, network instability, firmware settings, or a voltage or PSU issue. Compare local 10-minute, one-hour and 24-hour averages rather than judging from the startup reading.
When the KS3 may or may not fit
A KS3 is worth evaluating only when the buyer can verify the exact unit, price it with all delivery and installation costs, and model operations using current network and KAS inputs. Reliable low-cost power, adequate infrastructure and a repair reserve improve the case; none removes cryptocurrency or hardware risk.
Quick Recap
- Consider it: a verified, discounted unit; suitable 200–240 V infrastructure and airflow; electricity low enough to leave room after all operating costs; and acceptance of KAS-price, difficulty, downtime and resale risk.
- Reconsider it: a seller who will not provide a serial number or operating evidence, an improvised electrical setup, expensive cooling, a fixed-ROI promise, unclear return terms, or a purchase price that leaves little room for ASIC depreciation.
- For a home setup: treat power, heat and noise as installation constraints, not details to solve after delivery.
- For an investment decision: compare the machine with a newer ASIC and buying KAS directly using the same capital and risk assumptions.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
