E6400 BIOS forces fan off - 0 RPM all time

Hi, I had very frustrating experience with BIOS Thermal Control Panel lately.

I've been experimenting with Fn + 15324 (which decision now I regret), disabling BIOS thermal control and setting the speed fan manually. Usually everything resets after I reboot the laptop and everything was fine.

But last night reboot, didn't trigger the fan to start at all. The CPU temperature could reach 60-70 celsius degree, and fan is still indifferent and completely off. Now, I know this is not an hardware issue, because I can disable BIOS thermal control in Thermal Control Panel, and set the speed manually up to 5000 rpm, and the fan kicks in fast and smooth. But as soon as I enable the BIOS thermal control, the BIOS automatically force the fan speed at 0 RPM, regardless high temperature, and keeps it that way indefinitely.

I tried to restore default settings in BIOS F12, didn't work. Downgraded the BIOS one version, with hope to reset the BIOS settings or thermal tables, no luck. Upgraded still no luck. I'm out of options. Any help would be greatly appreciated.

Right now, I'm using i8kfangui to automatically manage fan speed according to temperature. It's not that bad, but I would prefer BIOS automatic control in certain occasions.

 

Maybe try to pull out the CMOS battery and plug in back in. Try to restore the bios settings into all default after. (Make sure the SATA operations settings remains the same)

 

Thank you for your reply, but I can't pull out CMOS battery because the case is sealed from the seller to preserve the warranty. If I open the case and destroy warranty tag then I lose the warranty.

 

I fixed it accidentally. Attention to dell users, If you turn off your laptop holding power button for several seconds while Fn+15324 is enabled, it can mess and corrupt thermal tables. The way I accidentally fixed it is to turn off again holding power button while Fn+15324 is enabled and temperatures were high.

 

I have the same problem but unfortunately this solution is not working for me

 

Maybe a dead fan? What software and hardware changes did you make?