Dear Linux kernel and ALSA developers,

I am reporting an issue related to runtime power management support for the onboard Realtek audio codec on my desktop motherboard, which results in continuously high audio hardware power usage and increased idle system power draw.

*System Information:*

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Kernel: 6.8.0-64-generic x86_64

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Distribution: Linux Mint 21.3 Virginia

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Motherboard: MSI MPG Z390 GAMING PLUS (MS-7B51)

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CPU: Intel Core i5-9400F

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Audio Driver: snd_hda_intel

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Audio Codec: Realtek (likely ALC1220 or similar)

*Issue Summary:* The onboard Realtek audio codec does not enter runtime power management low-power states, causing it to remain at 100% power usage even when idle. This significantly contributes to my system's high idle power consumption (~160W total), despite low CPU and GPU draw.

*Detailed Diagnostics:*

1.

*PCI Audio Devices:*

text |00:1f.3 Audio device [0403]: Intel Corporation Cannon Lake PCH cAVS [8086:a348] (rev 10) 03:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 31 HDMI/DP Audio [1002:ab30] 07:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Navi 21/23 HDMI/DP Audio Controller [1002:ab28] |

2.

*Kernel Messages related to snd_hda_intel or audio:* No logs found via|dmesg | grep -i snd_hda_intel|or|dmesg | grep -i audio|.

3.

*Power management sysfs settings:*

text |cat /sys/module/snd_hda_intel/parameters/power_save 10 cat /sys/class/sound/hwC*/power/runtime_status unsupported unsupported unsupported cat /sys/class/sound/hwC*/power/control auto auto auto |

The|runtime_status|reports "unsupported", indicating no runtime PM support is available for these audio devices.

4.

*PulseAudio and user-space processes inspection:* Stopped PulseAudio and all audio clients, with no change in power usage or device ownership of audio controls, confirming this is not caused by user-space audio applications.

5.

*Powertop Reports:*

text |100.0% Device Audio codec hwC2D0: Realtek |

Consistently 100% usage from the Realtek audio codec, confirmed by powertop.

6.

*Driver parameter set:* |snd_hda_intel|module|power_save|parameter successfully set to 10 seconds (value 10), but no effective power saving observed.

*Impact:* The lack of runtime power management support for this audio codec causes continuous high power draw, increasing system idle power consumption significantly, reducing energy efficiency.

*Request:* Please investigate whether this is a driver limitation, missing firmware quirk, or configuration issue with|snd_hda_intel|on the MSI MPG Z390 GAMING PLUS motherboard's Realtek codec. Guidance, workarounds, or patches to enable runtime power management would be appreciated.

*Additional notes:*

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Tested power management settings according to current best practices.

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BIOS is up to date as of the latest MSI release.

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System behavior consistent on Live USB of the same Linux Mint version—problem not due to local configuration.

Thank you for your attention to this matter. I’m happy to provide additional logs or assist with testing patches.

Best regards,

Thomas van Houten