Why does your ASIC miner keep restarting, and how can you fix it?

29 September 2026

Your mining/asic-miner-errors-troubleshooting-guide/">ASIC miner restarts because something in its environment, power supply, or configuration is pushing it beyond its safe operating limits. The fix usually involves checking your power source, network stability, or cooling - in that order. Below is a systematic breakdown of the most common causes and the steps to resolve them.

Power supply issues

The most frequent cause of sudden restarts is inconsistent or insufficient power. ASICs draw a lot of current, and even a brief voltage drop can trigger a reboot.

Check your outlet and circuit

• Ensure the miner is plugged directly into a wall outlet, not an extension cord or power strip designed for lower loads. Use a heavy-duty power distribution unit rated for the miner’s wattage.
• Verify the circuit breaker isn’t near its limit. A single Antminer S19 (around 3250W) can draw 13-14 amps at 240V. If other devices share the same circuit, the voltage may sag.
• Measure the voltage at the outlet under load with a multimeter. Any reading below 200V on a 240V circuit (or below 100V on a 120V circuit) is suspect. If voltage drops more than 10% when the miner runs, call an electrician.

Inspect the power supply unit (PSU)

• For miners with built-in PSUs (like Bitmain’s APW series): listen for clicking relays or fan noise that cuts out. A failing PSU can deliver erratic power even if it still lights up.
• For external PSUs: check all cables are fully seated. Loose PCIe or 6-pin connectors cause intermittent shutdowns. Swap cables from a known working PSU if you have one.
• A PSU that feels excessively hot to the touch or smells of burning insulation is failing. Replace it immediately - do not attempt repairs.

Network and pool communication

A miner that loses contact with its pool may restart the mining software to re-establish connection. This looks like a full system reboot but is actually a software restart.

Test your connection

• Ping your mining pool’s URL from a computer on the same network. High latency or packet loss (over 5%) suggests a network problem. Try a different pool server or use a wired Ethernet cable instead of Wi-Fi.
• Check your router’s logs for dropped connections. Some routers throttle or disconnect devices that use high bandwidth consistently. Assign the miner a static IP address or enable port forwarding if your router requires it.

Review pool configuration

• Ensure the pool URL, port, and worker credentials are correct. A single typo can cause the miner to repeatedly fail to authenticate, triggering a restart.
• Some pools require a specific stratum protocol (e.g., stratum+tcp:// vs. stratum+ssl://). Using the wrong one may cause the connection to drop after a few seconds.

Overheating and thermal protection

ASICs have built-in temperature sensors that shut down the unit before damage occurs. If your miner restarts after running for 5-15 minutes, overheating is likely.

Measure ambient temperature and airflow

• The intake air temperature should stay below 35°C (95°F). Many miners throttle or restart above 40°C (104°F). Use an infrared thermometer to check the exhaust air - if it exceeds 80°C (176°F) at the hashboard outlets, cooling is inadequate.
• Ensure at least 30 cm of clearance on the intake and exhaust sides. Recirculating hot air (e.g., stacking miners too close together) raises ambient temperature and triggers restarts.

Clean the miner

• Dust buildup on heat sinks and fans reduces cooling efficiency. Power down, remove the shell, and use compressed air (or a soft brush) to clean all hashboards and fans. Pay special attention to the gaps between aluminum fins.
• Replace any fan that wobbles, makes grinding noise, or runs at full speed constantly without cooling the miner.

Firmware or configuration problems

Miner firmware can also cause unstable behavior, especially after an update or if overclock settings are too aggressive.

Reset to factory defaults

• Access the miner’s web interface, navigate to the settings page, and choose “Factory Reset” or “Restore Defaults.” This clears any overclock profiles, custom fan curves, or voltage adjustments that may be unstable.
• If you can’t reach the web interface, use a paperclip to press the reset button on the miner’s control board for 10 seconds while powered on.

Update firmware only from official sources

• Download the latest stable firmware from the manufacturer’s website. Third-party firmware (e.g., Braiins, VNish) can improve performance but may require careful tuning. If restarts began after installing custom firmware, revert to the official version.
• After updating, verify the hash rate matches the miner’s spec sheet. A hash rate that is 20% or more below normal can indicate a hardware issue that will cause eventual restarts.

Hardware failure

If none of the above steps resolve the problem, the miner likely has a failing component - usually a hashboard, control board, or PSU.

Isolate the faulty board

• In the miner’s web interface, check the hash board status. A board that shows zero hash rate, frequent errors, or temperature readings far different from the others (e.g., 30°C while others are 60°C) is likely defective.
• Physically remove one hashboard at a time and run the miner with fewer boards. If the restarts stop, the removed board is the cause. Replace it or send the unit for repair.

Test with a known-good PSU

• If you have access to another miner, swap the PSUs. A PSU that passes a multimeter test can still fail under sustained load. This step is the most reliable way to rule out power problems.

When to stop troubleshooting

If your miner restarts more than once every 24 hours after you’ve tried all the steps above, the unit likely has a hardware fault that requires professional repair. Continued operation risks permanent damage to the hashboards or control board. Search for “ASIC repair service” near your location or contact the manufacturer’s support for your specific model.

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