Hi!
Before anyone else says it, here you’ll find how to provide good information!
The output of inxi -Fazy could be useful in this situation.
Now, I had a similar issue and discovered that one of the cores on my CPU was always busy handling ACPI interrupts.
Run and post the output of this command: grep . -r /sys/firmware/acpi/interrupts/ and look for excessive high values. The numbers you see should be 0 or little over 100, if you see something in the order of thousands we maybe found your problem and I’ll tell you how to solve it!