CPU throttled to 400MHz on Linux 6.14.4 + 258V

[yikerman]

I'm on an ASUS Zenbook S 14 (UX5406SA, with Intel Core Ultra 7 258V). Normally my CPU's thermal profile is as follows:

~> cpupower frequency-info
analyzing CPU 4:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 4
  CPUs which need to have their frequency coordinated by software: 4
  energy performance preference: balance_power
  hardware limits: 400 MHz - 3.70 GHz
  available cpufreq governors: performance powersave
  current policy: frequency should be within 400 MHz and 3.70 GHz.
                  The governor "powersave" may decide which speed to use
                  within this range.
  current CPU frequency: 1.90 GHz (asserted by call to kernel)
  boost state support:
    Supported: yes
    Active: yes

However quite randomly, it will be throttled to only 400MHz:

~> cpupower frequency-info
analyzing CPU 6:
  driver: intel_pstate
  CPUs which run at the same hardware frequency: 6
  CPUs which need to have their frequency coordinated by software: 6
  energy performance preference: balance_power
  hardware limits: 400 MHz - 3.70 GHz
  available cpufreq governors: performance powersave
  current policy: frequency should be within 400 MHz and 400 MHz.
                  The governor "powersave" 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

I've read about BD_PROCHOT. However both before and after the bug, sudo rdmsr 0x1FC reports e4005b; plus the issue does not exist in Windows on the same laptop. Where should I even start solving this issue? if this is some Linux firmware bug, where should I report it?

 

[gtrguy]

That’s not the normal power saving state?

 

[cyberblogger]

I've read about BD_PROCHOT. However both before and after the bug, sudo rdmsr 0x1FC reports e4005b; plus the issue does not exist in Windows on the same laptop. Where should I even start solving this issue? if this is some Linux firmware bug, where should I report it?

What distribution you are using? Because some distributions have already fixed this.

if its a systemd based linux, you can apply this:
make the correct pstate service:

sudo nano /etc/systemd/system/intel_pstate_setup.service

add this inside:

[Unit]
Description=Set maximum performance to 95% and min performance to 50%

[Service]
Type=oneshot
ExecStart=/bin/sh -c "echo 95 > /sys/devices/system/cpu/intel_pstate/max_perf_pct; echo 50 > /sys/devices/system/cpu/intel_pstate/min_perf_pct"

[Install]
WantedBy=multi-user.target

I just disable it myself as cpu scaling is a bad concept.

 

[1.1.2.3.5...]

sudo nano /etc/systemd/system/intel_pstate_setup.service

I am infinitely frustrated with nano, atom, etc.... vim or emac or gedit if those are too hard.