Using a Lenovo Legion Y520 with i7-7700HQ (base clock 2.8Ghz) and GTX 1050.
I'm getting CPU overheating warnings in linux and it's affecting my performance in games (found in Payday 2 and CS:GO). I've never had problems in Windows.
This is what I found when trying to troubleshoot this issue:
In Windows 10 (using aida64)
Windows stays at around 3.4 Ghz on idle (no idea why this is so high with less than 3% cpu usage), with a temperature of around 50C.
When stressing the cpu, the temperature goes slowly from about 50C to around 75C and stays there comfortably. Clock speeds are about 2.9Ghz when stressing. Utilization is always 100%. Aida64 doesn't report throttling. The voltage on the CPU core coes from about 1.1 to 0.9 when stressing.
In Arch Linux (using s-tui)
Linux stays at around 2.0Ghz on idle, with a temperature of around 50C.
Here's where it gets weird: when stressing the cpu, the temperature IMMEDIATELY goes from 50C to about 93C. Clock speeds are exactly 3.4Ghz when stressing. Utilization is always 100%. When turing the stress test off, the temperature IMMEDIATELY goes back to about 50C, as if nothing ever happened. The laptop certainly doesn't feel like it heats up to 90C+ when doing this, even after a long stress.
How do I fix this throttling issue? Do I undervolt my CPU in linux? How come it reads temperatures wrong in Linux but not in Windows?
I changed the profile using cpupower from powersave to performance. I still see the same throttling in s-tui. There is a jump up in idle cpu frequency when setting to performance (instead of around 2000-2500Mhz to always at 3400Mhz), but that's the only thing that has changed.
I tried to control fans using fancontrol (lm_sensors), but pwmconfig says there are no pwm-capable sensor modules installed.
I tried it with NBFC, but it doesn't seem to be doing anything, no matter what profile I choose. I don't even know if NBFC can control my fans, but it doesn't report any errors when choosing a profile.
I also tried thinkfan, which can control my fans, but it doesn't seem to help with throttling.
I found that lowering the maximum allowed cpu frequency using cpupower to something like 3100MHz instead of the default 3800 fixes all issues.
sudo cpupower frequency-set -u 3100MHz
I also changed max_freq in
/etc/default/cpupower to the same value, to make it permanent. I found that this does result in a slight fps drop in games, but nothing serious. At least my fps is stable :)
Sadly I think this might result in decreased performance in non-gaming tasks like when compiling something.