Question 3yo ASUS Zenbook UX430UAR fan at 100%

[Eloking]

3yo ASUS Zenbook UX430UAR CPU fan at 100% (over 6000rpm) at startup in UEFI, CPU at 35°C

So our 3-year-old ASUS Zenbook UX430UAR recently decided to put the CPU fan at +6000 rpm at startup for no reason whatsoever.

-It's not CPU (some Intel i5) related as the temperature of all 4 core well below 35°C (95°F). It also discards dirt as it would cause the CPU to overheat then forcing the fan to start, it's not the case.
-It's not Windows-related as the fan kick in as soon as you press the power button and even if you enter the BIOS.
-The BIOS is updated to the latest version (308). All drivers have been installed (again, since it happens in the BIOS, no driver should be related).
-I tried to install SpeedFan but it doesn't seem compatible. The option to change the fan speed doesn't appear.

I'm starting to wonder if there's some grease or something that I could add to the fan to mechanically keep it from going that fast.
Help me out, please?

 

[Lutfij]

Welcome to the forums, newcomer!

You shouldn't look at lubricating the fan's bearings when the issue since the issue is only confined to the booting stage of the laptop/OS(going along with what you've stated). You can try and remove battery power from the laptop and then press and hold the power button for 30 seconds before replacing the battery to see if clearing the CMOS changes your experience.

What OS version are you currently on?

 

[Eloking]

Thanks for the quick answer Lutfig, greatly appreciated.

The Zenbook is running stock Win10 x64 with the latest update. Curious how it could be related since the fan goes at 100% before the OS boot. Just so I'm clear, as soon as you press the power button the fan goes at +6000 rpm and stay stable at the speed until I power it down.

Opening a Zenbook to access the battery connector may prove difficult since thise Ultrabook doesn't have a swappable battery but I'll look it out. Any ways to do it without this process?

Finally, the objective of the grease isn't to lubricate it. Quite the opposite actually, I want to mechanically force it to throttle down. But I'm not too serious about it since there's a high probability that I will kill the fan. Maybe adding a resistor to the wire to lower the fan voltage?