I am using a AMD RX 7800 XT and noticed that my idle power consumption has went up recently from ~5-10W to ~30W. After some investigation I found out it was caused by the change to the default power profiles from BOOTUP_DEFAULT to 3D_FULLSCREEN in 6.13. When in 3D_FULLSCREEN profile, the GPU memory clock won’t transition to the lowest clock speed and consuming extra ~20W (!!) of power.

To fix this, I have to manually change the power profile using following commands (as root):

echo 'manual' > /sys/class/drm/card1/device/power_dpm_force_performance_level
# check the available power profiles to get the index
cat /sys/class/drm/card1/device/pp_power_profile_mode
# normally 0 = BOOTUP_DEFAULT
echo 0 > /sys/class/drm/card1/device/pp_power_profile_mode

(you may need to change card1 to card0 depends on your system)

Note that the configuration is not persisted across reboot and you may encounter shuttering during gaming with BOOTUP_DEFAULT.

I recommend to use tools like LACT to automatically apply the power profile on startup and also automatically switch the profile to 3D_FULLSCREEN when running games.

Edit: you should check you current GPU idle power consumption first (with nvtop or lm_sensors) before applying the change, the issue may not affect all AMD GPU

  • grue@lemmy.world
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    7 hours ago

    Huh interesting. Are these displays all the exact same model?

    Yep. I like me some symmetry.

    I’m not sure if this is expanded further with RDNA 4 but I can try to find out.

    Thanks very much; I would love to have all three displays freesyncing!

    • Vik@lemmy.world
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      26 minutes ago

      I don’t believe FPO was expanded to >2 displays, though having identical panels would eliminate VBI complexities. Will be interested in understanding how this behaves with rdna 4.