I have a cpu fan that revs up and slows to a stop every 15 or so seconds even when pc is idle.

[Dutch1009]

I get a cpu fan not operating properly on bootup error message 90D. CPU fan revs and slows to stop every 10-15 seconds. cpu not overheating stays between high 70s to low 80s F.

[praveenbv]

@Dutch1009,

I reviewed your post and I understand that you are getting a system fan error 90B on the computer.

Don’t worry, I assure you I will try my best to get this sorted.

I recommend you update the BIOS from the below link and check whether the issue is resolved.

HP Pavilion Desktop - 510-p017c

If the issue persists, then continue troubleshooting from the below article.

https://support.hp.com/in-en/document/c03620929

Hope this helps! Keep me posted. 

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