Why do my computer fans start then stop?

Experiencing the issue where your computer fans start then stop can indeed be maddening. In my experience, the solution often revolves around a few common culprits. Let’s dive into the analysis.

1. Power Supply Complications:
   A degraded or insufficient Power Supply Unit (PSU) is a prime suspect. The PSU might be unable to supply consistent power, leading to the erratic behavior of the fans. To check if the PSU is at fault, try using a different but reliable PSU.

2. Motherboard Sensor Troubles:
   The sensors on your motherboard might be defective or miscommunicating the cooling instructions. Inspect your motherboard for any visible damage and ensure all BIOS settings are accurate. You might need to update the BIOS firmware to tackle this issue.

3. Thermal Management Issues:
   Your system’s thermal management might be misreading temperatures. Utilize monitoring tools like HWMonitor or SpeedFan to track temperature fluctuations. If overheating or sudden temperature drops occur, it might cause the fans to shut off.

4. Physical Dust Obstruction:
   Accumulated dust can obstruct the free movement of the fan blades. Regular cleaning of the internals can prevent this issue.

5. Driver and Software Conflicts:
   Ensure that your drivers, particularly those managing the motherboard and cooling system, are up-to-date. Outdated or corrupted drivers can cause the system to malfunction.

Addressing these areas thoroughly should provide a significant headway in resolving the problem. If the issue persists, a technician’s assistance might be required for a more detailed diagnosis.

I’ve encountered the issue of computer fans starting and stopping multiple times in various builds, and it can boil down to a few key points.

1. Power Supply Problems:
   Check if your PSU is working correctly. A faulty PSU can cause power inconsistencies, making the fans start and stop. Swap with a known good PSU to test.

2. Temperature Control Misconfiguration:
   Enter the BIOS and check that the fan settings are set to automatic mode. Incorrect settings can cause improper fan behavior.

3. Dust and Debris:
   Internal grime can obstruct fan movement. Thoroughly clean the inside of your case.

4. Driver Issues:
   Make sure all drivers, especially for the motherboard and cooling systems, are up to date. Driver conflicts often cause erratic behaviors.

When computer fans start then stop suddenly, it could be due to several underlying factors. Here are some possibilities and actions you can take to resolve them.

1. Faulty Power Supply Unit (PSU):
   The PSU might not be delivering stable power. To diagnose, try using a PSU from another system or a new one known to function correctly.

2. Misconfigured BIOS Settings:
   Check if fan control settings in the BIOS are set to automatic and not manually overridden. Restoring defaults can sometimes fix this.

3. Temperature Sensor Issues:
   Faulty sensors can send incorrect signals. Monitoring software can help you verify temperature readings.

4. Loose Connections:
   Ensure that all power cables are firmly connected and components properly seated. Loose connections often cause inconsistent power delivery.

5. Obstructions And Dust:
   Clean the internals of your PC. Dust can impede fan movement, causing them to stop abruptly.

Updating firmware and drivers, another common fix, ensures all hardware communicates properly. If these suggestions don’t resolve your problem, professional help could be necessary.

When your computer fans start then abruptly stop, I’d recommend checking the following:

1. Inconsistent Power Supply:
   Ensure your PSU is not failing. It needs to provide steady power.

2. BIOS Fan Control Settings:
   Incorrect BIOS settings can cause fans to behave erratically. Reset to default or adjust settings in BIOS.

3. Overheating,:
   Monitor the system’s temperatures with software tools to see if it’s a response to overheating.

4. Physical Obstructions:
   Inspect for and clear any dust or debris blocking the fans.

Make sure to monitor these areas closely to identify where the problem might be.