You specifically ask about speeding up the CPU but without risk to the CPU or other parts. The manufacturer of a motherboard is looking for long life and reliable operation at the highest possible speed. It may well be possible to overclock a system to increase speed but the system will run hotter. Extra heat is likely to reduce component life time, decrease reliability and will need extra cooling just to operate.
The thread below is mainly about slow booting. It covers things like disabling startup services and fixing the system IP address to reduce startup time.
But a system that is slow to boot will generally be slow to run and the post explains that old hardware is the main limiting factor on performance so is worth reading.
https://www.linuxliteos.com/forums/start-up-and-shutdown/slow-boot-times-in-linux-lite/The most commonly recommended performance improvements - upgrading CPU, adding extra RAM, changing a mechanical disk to a solid state disk - require hardware changes.
I think from your other posts that you have a system manufactured in 2009. If you aready have 16GB RAM and an SSD you may already have done the easy improvements.
Thread moved to hardware.