See Gentoo:Ryzen#Random_reboots_with_mce_events if you are experiencing random reboots. The officially supported kernels have the required configuration by default. See Gentoo:Ryzen#Kernel on enabling Ryzen support. A detailed setup example is given in Level1Techs forum.

ZenStates-Linux - ZenStates is a command-line tool to adjust the clock speed and voltage.

amdctl - amdctl is a command-line tool for under/over clocking/volting AMD CPUs, currently supporting AMD CPU families 10h, 11h, 12h, 15h, 16h, 17h and 19h.

Ryzen Controller - Ryzen Controller is a GUI for RyzenAdj.

RyzenAdj - RyzenAdj is a command-line tool that can adjust power management settings for Ryzen mobile processors.

Power management, undervolting and overclocking For GUI based monitoring tools, use zenmonitor AUR or zenmonitor3-git AUR for Zen 3 CPUs. However, for more detailed information such as power consumption and voltage, zenpower3-dkms AUR is needed. Lm_sensors should be able to monitor temperatures out of the box. Tweaking Ryzen Voltage, power and temperature monitoring It is highly recommended to use it despite it being proprietary. These updates provide bug fixes that can be critical to the stability of your system.

Install the amd-ucode package to enable microcode updates and enable it with the help of the Microcode page.

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