Score:0

Intel tiger lake CPU not downclocking

cn flag

I have Kubuntu 21.10 installed on an HP laptop with a core i5 11th generation. The problem is that battery drains faster than it should. After investigating the issue it turned out to be the CPU not downclocking at idle causing power waste. I tried changing CPU scaling governor, setting maximum frequency manually but the CPU seems to be ignoring all of this and sticking to 1.6GHz+ frequencies no matter what (I even tried acpi-cpufreq but no luck).

As a last resort, I used system76-power to set power profiles, it gave an error stating that it could not set platform power profiles (OS error 95) when run in daemon mode.

How can I fix this issue?

TD15 avatar
cn flag
I'm on Kubuntu so there are several power options. On plasma 5.23 setting power manager to power save still doesn't do much.
us flag
Try `sudo apt install tlp` and `sudo tlp start`. TLP is a program to make the computer use its resources efficiently so that it can last longer on battery.
in flag
Did you disable the Intel P-state power manager when you installed `acpi-cpufreq`? If not, then any settings you configured would have likely been ignored
TD15 avatar
cn flag
In the default grub configuration, I added the command intel_pstate=disable and updated grub before trying acpi-cpufreq. Still no luck. Is it possible that powertop is reporting incorrect frequencies? I also tried powertop and TLP, no noticeable difference.
Doug Smythies avatar
gn flag
How fast does the battery drain? CPU frequency by itself does not explain things. We also need to know active verses idle times. What is your exact 11th gen i5 model number? If you do not want to use the intel_pstate driver, then I suggest the intel_cpufreq driver without HWP. grub: `intel_pstate=passive intel_pstate=no_hwp`. I always suggest using turbostat (linux-tools-common package, I think). `sudo turbostat --Summary --quiet --show Busy%,Bzy_MHz,IRQ,PkgWatt,PkgTmp,RAMWatt,GFXWatt,CorWatt --interval 10` and would like to see output for a couple of minutes.
TD15 avatar
cn flag
Sorry for the late reply. I first tried running the turbostat command before changing anything in grub. The CPU package at idle uses 1.7-2.5 W only. I think there are other factors involved here. Thanks for the help @DougSmythies
Doug Smythies avatar
gn flag
Agreed, processor energy consumption seems normal. Look into graphics energy use, which I know nothing about because I am a server person.
Esther avatar
es flag
does this laptop by any chance have a higher-resolution monitor than the lower-power one? That can use a lot of power. Maybe edit to include the exact models of the power-hungry and ok laptops
sancho.s ReinstateMonicaCellio avatar
Please add *in the question* all the information that supports your statements and describes your actions: 1) How do you know that "battery drains faster than it should"? 2) How do you know that "CPU not downclocking at idle"? 3) How did you try "changing CPU scaling governor, setting maximum frequency manually"?
TD15 avatar
cn flag
Followup on the situation: I disabled battery time reporting in BIOS settings and somehow the battery is actually lasting double the time before the change. Sounds like HP has something messed up in their BIOS
Esther avatar
es flag
That is probably something you should report to HP, and also check if there is a newer BIOS available for your device
TD15 avatar
cn flag
I checked if a BIOS update is available and I have the latest one. I will have to check how to report to HP or even if they would accept the report because the issue didn't use to happen on windows (before I removed it), and HP does not provide support for Linux
sancho.s ReinstateMonicaCellio avatar
You should add all information in the question, suitably organized for the readers to quickly understanding it. In the end, the one who will take the most advantage of that is you.
TD15 avatar
cn flag
Compared to another laptop with a U series processor, the energy usage is almost +1-1.5W while idling.
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.