CPU slows down as soon laptop unplugged, stays slow even if plugged back in

Yeah. Good thing I’m not constantly switching, and the workaround is simple.

Also, thanks a lot for your help, I really wouldn’t have gotten this far without you :slight_smile:

see this topic

I just created a forum account to share something that may be useful.

I had the exact same problem and it was noticeable while playing demanding games during intermittent electric outages.

sudo cpupower frequency-set --max does work well, but I found that the problem was a mis-configuration in my TLP config (/etc/tlp.conf). Even if I disable TLP and restart the system, the problem persists because of that mis-configuration.

The following block was causing the problem:

CPU_SCALING_MIN_FREQ_ON_AC=0
CPU_SCALING_MAX_FREQ_ON_AC=0
CPU_SCALING_MIN_FREQ_ON_BAT=0
CPU_SCALING_MAX_FREQ_ON_BAT=800000

After changing it to the following (notice the explicit max AC frequency):

CPU_SCALING_MIN_FREQ_ON_AC=0
CPU_SCALING_MAX_FREQ_ON_AC=4000000
CPU_SCALING_MIN_FREQ_ON_BAT=0
CPU_SCALING_MAX_FREQ_ON_BAT=800000

… and restarting the TLP service (sudo systemctl restart tlp), the problem was fixed.

Hope this helps.

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