To check your GPU's P-states, execute:

$ cat /sys/class/drm/card0/device/pp_od_clk_voltage

To monitor your GPU, execute:

$ watch -n 0.5 cat /sys/kernel/debug/dri/0/amdgpu_pm_info

To check your GPU utilization, execute:

$ cat /sys/class/drm/card0/device/gpu_busy_percent

To check your GPU frequency, execute:

$ cat /sys/class/drm/card0/device/pp_dpm_sclk

To check your GPU temperature, execute:

$ cat /sys/class/drm/card0/device/hwmon/hwmon*/temp1_input

To check your VRAM frequency, execute:

$ cat /sys/class/drm/card0/device/pp_dpm_mclk

To check your VRAM usage, execute:

$ cat /sys/class/drm/card0/device/mem_info_vram_used

To check your VRAM size, execute:

$ cat /sys/class/drm/card0/device/mem_info_vram_total