fan only spin at around 4200 RPM

[JMF11]

Dear all,

I recently changed the fan of my laptop (it seemed to have a bearing problem and was making a strange noise). I bought a new fan on ebay and fitted it to the existing heatsink. When I restarted the laptop, I felt that it was much more noisy than before.

It took time to figure out what was hapening. I installed tpfc and I understood that:
- the fan RPM sensor seems to provide relevant information,
- CPU/GPU temperatures are OK,
- but whatever the fan level in tpfc (from 1 to 7), the fan runs at around 4200 RPM (this in BIOS, smart or manual mode).

So there no low speed/low noise mode, which I had previously. Only a fast noisy one...

I have the last BIOS version. And the only mod was the fan replacement.

Would you have ideas about what happens ? how to troubleshoot ?

This is a R61, but the issue may be similar to behaviours encountered on T6x, and the community is much bigger.

Thanks for your help.

Kind regards,

JMF