Fan always on when charging (Spectre x360 8th gen)

[BasW01]

I've now done a couple of things to prevent the fans from coming on. 

- I try to be careful with the amount of load I put on the CPU so it doesnt get too hot. 

- Of course install the latest updates

- In the power plan, under the battery tab, I changed the max CPU usage to 99% instead of 100%. I read somewhere on the forum that this should keep the CPU from using turbo boost.

- Also in the energy plan under energy mananagement for processor, I changed the cooling plan (? dont know what its called in english) to passive for battery and plugged in.

I dont know if the laptop is new, but I noticed that in the first week the fan kicked in because of all the updates it was downloading.  Since then, because I am careful I suppose, the fan hasn't come on anymore.

If the CPU keeps kciking to 3.7GHz when charging, I would look into the power plan settings first. Hope this helps in any way.

[Induna]

The reason the fans behave the way they do when plugged in and not when on battery is pretty straight forward. The cooling solution is designed to let the processor reach high temperatures without turning on the fan. However, once the case temperature reaches a certain level, it seems to be 85C or so, the fans will turn on and will not turn completely off until the case temperature drops below around 45C. While on battery, the CPU is limited to 15W. With only 15W of heat to disipate, the case temperature will only reach 85C under sustained, moderate to heavy loads, and will then cool off relatively quickly.

On AC power, however, the short term power limit is raised to 30W. This allows the CPU to boost on all 4 cores to around 3.4GHz. This produces a lot of heat very quickly. Even when the sustained load on the processor is low, it may still be boosting very high for short periods. This produces enough heat to keep the case temperature above the fan shutoff point for extended periods. In addition, certain processes, like updates, virus scans, etc. often automatically use more resources when on AC power, producing more heat, and keeping the fans on.

Undervolting helps performance, but doesn't really change this behavior. Using the XTU utility to reduce the short term turbo power limit should help conciderably, at the cost of some performance. There are several threads on Reddit about this.

[david_sanches]

I found a solution. Just with a bios update the problem is solve.

[ajinugi]

Which BIOS are you referring to? Is it the F.15 Rev.A dated Feb 26, 2018?

I've installed that BIOS, but the problem persists.

[MateoLara]

What version of the BIOS are u using because I still having the problem with the fans and I have the last version of the BIOS

[david_sanches]

The version is: AMI f15 22/02/2018  (Maybe it is a Spanish version)

But lately I have been sufering the same issue ... So this did not solve the problem as I thought It did.