Hey guys, I am posting this as a continuation on an old thread of mine about my severe slowdown on ac that I had for many time...So lets recap: I have a hp 15s laptop with intel i5 and for a long time now, my laptop was throttling extremely on AC. Basically once it starts charging it slows down making me unable to work efficiently...It literally lags to the point where gnome menu wont animate and on boot, it refuses to continue only after I disconnect the charger...Even worse sometimes I will be waiting for about 1 second delay while typing. I have to note that I have an nvme SSD and 16GB ram so I never quite expected this. I heard modifying my grub configuartion and enabling intel_pstate will make a change, but it didnt.
Every 1.0s: cat /proc/cpuinfo | grep MHz hp-15s: Sun Oct 19 22:55:16 2025
cpu MHz : 400.049
cpu MHz : 400.054
cpu MHz : 400.050
cpu MHz : 400.051
cpu MHz : 400.003
cpu MHz : 400.008
cpu MHz : 400.013
cpu MHz : 400.000
cpu MHz : 399.999
cpu MHz : 400.007
cpu MHz : 400.022
cpu MHz : 400.010
which as you can see 399Mhz is unecceptable...I tried using tlp which didnt help. I also have to note that if it is above 94% it will work fine no matter on AC or not and even if sometimes some cpus will actully rise, most of them especially the first, will stay at 400Mhz and it slows like hell. And the weird part of all this is that my collegue from university who bought the exact same laptop same link (my friend used mint), never had problems like this...And ever weirder is that when I booted to linux mint as well as zorin on live usb when it had the symptoms, nothing changed. Even updating the kernel to 6.16.3-76061603-generic didnt make a difference at all. Basically when it has theese symptoms when charging, it refuses to rise its frequency above 400mHz which is basically the minimum hardware limits. I also have to note that testing my cpu tempreture gave me normal results around 43 degress celsious
andronikos@hp-15s:~$ cat /sys/class/thermal/thermal_zone*/temp 43000 20000 12050 41000 43000 43000
andronikos@hp-15s:~$ cpupower frequency-info analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 energy performance preference: performance hardware limits: 400 MHz - 4.40 GHz available cpufreq governors: performance powersave current policy: frequency should be within 2.50 GHz and 3.30 GHz. The governor "performance" may decide which speed to use within this range. current CPU frequency: 400 MHz (asserted by call to kernel) boost state support: Supported: yes Active: yes
(Modifying the cpu frequency had no effect, it basically refuses to rise:
/sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq; do echo 2500000 | sudo tee $cpu; done
)
The only time where it didnt throttle was when i bootted a Windows USB. What do you think is the best thing to do?
If you both have the same laptop, are you able to swap your laptop battery with your colleague's laptop battery?
I am wondering if there is a voltage regulator or battery condition underlying this performance puzzle.
I dont know...I never asked him about it. I asked my cs teacher and he told me to try to update the BIOS, which I cant because I dont have a Windows computer anymore. Also I think a technician can only open the laptop and change the battery
Your CS teacher is correct. This is a firmware level issue where the ACPI-PSS call is incorrect, resulting in the wrong reading and PowerSave kicking in. This is not governed by the Linux Kernel.
It works on Windows because Windows has ACPI table code paths that can override it.
You Do Not Need to be on WIndows OS in order to update your BIOS Firmware.
Yes, many patches are released as .exe, but that is just a self-extracting executable.
There are many different ways you can do this... and which you choose depends on your comfort level and experience level. But if you do a net search for guides, you probably can find one that fits you.
And we can help step by step on the forum by reviewing a guide first; or confirming what you see with screenshots along the way.
@Aravisian
Sounds good to me...Well Im not yet comfortable with bios updates and I can only proceed with your help, step by step. Also I need to make sure that I can revert back if something goes wrong like for example if it gives me an error through this...And Im also a bit anxious about it because I read that even though hp laptops have a recovery bios image incase it goes wrong...mine doesnt...I pressed win+b+power for 3 seconds and Even though it was supposed to give me a accept prompt to reset the bios, I got a message that my laptop doesnt have a bios recovery file...
Maybe tommorow I will be free sometime...Basically I will tag you in the thread when Im ready to proceed, would this take alot of time?
That depends... the process itself is very simple. A terminal command can move a file along a long path in One Drop.
What you would be doing is a three step process:
Downloading the BIOS update from HP
Extracting it by any method you wish
copying the file to the /boot/EFI > directory path
Yes, because your fear is that an error can brick the machine - which that can happen.
The Good News to keep your heart rate down is that we can bypass that.
What that message means is that it has only one .bin file for BIOS - We will not overwrite or remove it - but instead add a new directory: /Hewlett-Packard/BIOS/New/
Doing it that way, leaving the old BIOS intact to fall back on, you won't have that worry. But, it will mean you need to have an empty USB stick at the ready to use.
The USB stick would need to be formatted to FAT32. In your File Manager on Zorin OS, you can create the directory tree /Hewlett-Packard/BIOS/New/
In that New folder, place the files we extract from the HP BIOS .exe file.
Then reboot the computer with the USB stick plugged in - Selecting to start from that stick.
Can you find a bios update link for my model?
I never did such a thing before and I dont know how
HP 15S-FQ5916NV 15.6" FHD Anti-Glare (Core i5-1235U/16GB/512GB SSD/Iris Xe Graphics/Win11Home) Laptop
I called a technician and he told me there is new bios update for my model...I dont rember the version he told me...
Now my BIOS version says its at f 22
My serial number is 5CD4375K6V
Then select your OS as Windows and the version as Windows 11
Below that click Submit
You will be taken to a page with drop down menu's - select BIOS
Then for the Vers. F25 - the Download Button on the far right.
searches for the .bin - if nothing is showing up, H.P. has it wrapped in a way that requires HP's Provided Tool to get at it.
I hate this devious petty soft blocking companies do.
I will need to look into this further...
If you are feeling impatient, though, you could just use Windows OS on a USB stick like Windows-To_Go or Tiny11
You cannot use WINE to perform any of this - that will brick things.
EDIT: Three easy steps! After jumping through one million hoops just to get the files...
