The fan is not operating correctly on bootup

[Kenm976]

I keep getting this error on bootup, CPU Fan error 90B. It happens about 80% of the time. Other than ship to HP any other suggestions?

[Riddle_Decipher]

@Kenm976 Due to the current global COVID-19 situation, we're seeing an influx of customers coming in for support and we appreciate your patience.

That said, When starting the computer, the system fan might spin faster and become louder, and one of the following error messages might display on the screen:

• The system has detected that a cooling fan is not operating correctly.

• Continued operation is not recommended and may cause unpredictable behavior that could result in random shutdown, data loss or possible system damage. The system will shut down in 15 seconds. To prevent shutdown and continue operation, press the Enter key now.

• System Fan (90b)

• System Fan (90f) This error indicates that a problem exists related to the heat removal system.

This message indicates that the system fan is not spinning at the expected speed or a problem exists related to the heat removal system. This message occurs to help prevent costly damage to the computer.

To fix this error, use the following steps:

1. Press Enter to clear the message and allow the system to boot to the Windows Desktop.

2. Shut down the computer, and then inspect and clean the exterior vents to remove dust buildup by blowing air through the vent openings. Dust can accumulate inside the vent openings and around internal cooling components, preventing the removal of heat.

   For more information on reducing heat inside your computer, see Reducing Heat Inside the PC.

3. After you remove the dust, turn on the computer. If the error message persists, continue with these steps.

4. Perform a hard reset. Performing a hard reset can reset recorded thermal values in memory and enable you to use the computer again, even if only for a short time to access and save any important files before service.

   For more information on performing a hard reset, see Use Hard Reset to Resolve Hardware and Software Issues.

5. In some cases, updating the BIOS might help prevent this error from occurring.

   For more information on how to update the BIOS, see Updating the BIOS.

6. Have the computer serviced to clean internal components and replace the system fan if necessary. Make sure to address the following items when servicing:

   • Thoroughly remove dust from all internal cooling components.

   • Make sure wires from the system and CPU fans are connected securely to the motherboard.

   • Confirm the system fan blades spin correctly, and the fan is not producing loud noises. If not working correctly, replace the system fan.

   • Remove old thermal compound from integrated circuits and heat sinks and replace with new thermal compound.

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