I’ve got a FW 13 AMD, running Arch Linux with Cinnamon desktop. My fan is usually off because my load is normally near zero. Running firefox with 10 tabs or so, and a few terminals, code editor, file browser, image viewer …
top - 14:02:56 up 3 days, 16:59, 1 user, load average: 0.26, 0.89, 0.85
Tasks: 350 total, 1 running, 349 sleep, 0 d-sleep, 0 stopped, 0 zombie
%Cpu(s): 0.6 us, 1.3 sy, 0.0 ni, 97.9 id, 0.0 wa, 0.0 hi, 0.2 si, 0.0 st
MiB Mem : 27866.5 total, 16200.0 free, 4035.5 used, 8318.4 buff/cache
It’s normal for modern “thin” laptops to operate at max speed only in very brief bursts: just for a second or so when you open an application, or navigate in a heavy website, etc. The CPU is capable of a lot more than the heatsink, and it is beneficial when very brief load spikes are processed faster, it makes things more responsive/snappy.
Re-pasting the heatsink, or switching to PTM on the heatsink, will probably help a bit. But if your regular set of daily apps idle above ~ 2% CPU usage, I’d consider that a software issue, and try to fix it. Figure out what apps are to blame, and disable the features that are loading your CPU when nothing’s really happening. There have been cases where some electron-based app has a blinking cursor that spins a cpu core under some condition. (15% load is just above 1 core out of 8!)
(Also, measuring load can be very tricky, as mentioned above. Modern CPUs do not go at one speed. Instruction set mixes vary. With SMT, half the cores are “logical” not “physical”, so in a sense, 50% overall cpu usage is much closer to 100% than to 0%. Modern CPUs have features that thus enable “bursting” performance whenever possible, in a few different ways, which can be very beneficial, but it’s not always possible. It varies greatly depending on the specific workload.)