11-11-2018 01:44 AM - edited 11-11-2018 02:01 AM
This is for the X1 Carbon 6th Gen.
There are a number of threads this post refers to:
My understanding is that the CPU idle frequency settings are set in Windows registries while the fan settings are set in the BIOS. The issues discussed below are for the laptop on AC, not on battery.
-People reported that the CPU idles at around 4GHz no matter what tasks are performed on the laptop, leading to excessive heat. Lenovo provided a solution that lowers CPU idle frequencies to approximately 0.86GHz, 1.66GHz, 4GHz for Better Battery, Better Performance, Best Performance power modes (not power plan) respectively. They incorporated this solution in an executable patch found here: https://support.lenovo.com/sa/en/solutions/ht506625
Reading the notes for the patch, I see under Operating Systems:
And further down, under Additional Information:
This issue is fixed in factory preloads based on Windows 10 1803 (version 17134) and later. Only factory preloads based on Windows 10 1709 (version 16299) had this issue. If the symptoms are not noticed, then it is not necessary to apply the solution.
Q1- Why is Windows 17134 mentioned if the problem only affects version 16299?
Q2- Does the executable include anything other than the three pwercfg commands mentioned in the post by @someotherguy?
Q3- Why isn't this patch available under the official Drivers & Software downloads page for the X1 Carbon 6th Gen?
BIOS release notes mention:
UEFI: 1.28 / ECP: 1.08 - release date 2018/08/24
- (Fix) Improve power control.
UEFI: 1.25 / ECP: 1.08 - release date 2018/06/29
- (Fix) Fixed an issue where ThinkPad surface temperature is higher than designed.
UEFI: 1.15 / ECP: 1.08 - release date 2018/04/19
- (Fix) Improvement of FAN rotation.
It is not clear to me whether all three affect fan rotation or only 1.15 does. Though a post here indicated that fan rotation settings are constantly being improved.
Q4- Can someone from Lenovo clarify if the three BIOS mentioned above affect 1- CPU frequency, 2- FAN rotation, 3-both?
Q5- Is any other BIOS other than those mentioned affecting 1- CPU idle or working frequency settings, 2- FAN rotation settings?
What I did
I have Windows 10 build 17134 as factory preload. I updated BIOS to 1.31 (release date 2018/09/28), from 1.15. I observed that the CPU still idles at 4GHz, no matter what power mode is selected. This does not tie in with the description in the patch fix for CPU mentioned earlier which states that this problem is already fixed in the factory for build 17134. I applied the three commands in Command Prompt to reduce CPU idle frequencies. I confirm that this behaves as described. Though the prior settings for those three items were not clear to me (the post mentions they were all set to 0).
It is not obvious to me that BIOS 1.31 modified fan rotation settings. I do hear a little coil whine now, I am not sure it was present before the BIOS update.
On AC, the laptop is somewhat quiet but does still feel warm. I find it to be much cooler on battery.
Related (but different?)
In addition to these two "fixes", there are downloads in Drivers & Software for this product which seem to also affect CPU and FAN settings, like in Power Management, Chipset, Software & Utilities categories like:
Lenovo Intelligent Thermal Solution Driver for Windows 10 (64-bit) - ThinkPad
Intel Dynamic Platform & Thermal Framework Driver for Windows 10 (Version 1709 or later) - ThinkPad X1 Carbon 6th Gen (Type 20KH, 20KG)
Lenovo Power Management Driver for Windows 7, 8, 8.1, 10 (32-bit, 64-bit) - Laptops
Lenovo Dynamic Power Reduction Utility for Windows 10 (64-bit) - ThinkPad X1 Carbon (Machine types: 20KH, 20KG)
Q6- Were these installed in the factory preload? Should I install them? Will I run into conflicting settings?
As a customer, I am a little lost in trying to make sense of it all. While it is informative and interesting to read and learn about these topics, I really don't feel that Lenovo customers can be expected to do this work or be associated to this extent in tuning the product and tinkering with it.