Help, Cpu stuck at 400 mhz for a couple minutes after long pc suspend

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Hi everyone,

I’m experiencing a frustrating power management issue on Fedora with my Lenovo Ideapad Slim 5, powered by an Intel i7-13620H (Raptor Lake).

If I leave the laptop suspended for a long period (e.g., 1-2 hours or more), the CPU is capped at exactly 400 MHz upon wake. During this state, the entire system is sluggish. After checking with turbostat I found the CPU Package Power is limited to roughly 4–5 Watts (Power: LIM). This “probation period” lasts for a couple of minutes, and then the wattage suddenly unlocks, jumps back to normal (15W–45W+), and everything feels fast again.

Crucially, this does not happen if the laptop is only suspended for a short time. Furthermore, I am dual-booting Windows on the same SSD and the problem never occurs there; after a long suspend on Windows, the CPU wakes up at full speed immediately.

I have already tried troubleshooting with the “throttled” service and disabling BD PROCHOT, but the initial 4W clamp still occurs right at wake-up.

Any help would be apreciated.

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You will need to say which Fedora you are on.
For example, if you are on Gnome, you could see how your Power Profiles is set - and change it to ‘performance’.

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I’m on Fedora 43 (KDE Plasma Desktop Edition). Linux 6.18.7-200. Everything is set on performance even in BIOS settings.

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