If this was in my lab I'd be sure to get a Speccy report so I can check out the BIOS and a lot of other items.
Your story is too light. Such as how old, did it ever work right and how you deal with BIOS and driver versions.
CPU N3700 does clock slow down but not more up, help
The problem is that the the laptop becomes slow, and the CPU can reach max 30%. This i scaused because of the frequency, instead of 2,4GHz can go and stay much lower.
I've tried to test and stress it, RAM, CPU stress/heat for hours, mechanical stress of plastic cover while working, all is good, can't figure out how this happens. Then I noticed that when the laptop is free of load, and for power save the cpu is slow down, it never more comes up. That looks the problem, a reboot can solve it, but I had a couple of situations that after power off, removed battery, pushed power button to discharge condensers, wasn't solved on the next reboot.
How can I force CPU work always?
Maybe an incompatibility between Win10 ACPI and laptop?
Thank you

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