Steam Machine Wake on LAN does not work from S4/S5

Your system information

• Steam client version: 1785799196
• SteamOS version: 3.8.16
• Opted into Steam client beta?: No
• Opted into SteamOS beta?: No
• Have you checked for updates in Settings > System?: Yes

Please describe your issue in as much detail as possible:

I recently received my steam machine and plan to use it primarily for streaming to my other devices. It is connected to my home-network via LAN.
Within the BIOS i activated the option S4/S5 Wake on LAN Support and also instructed nmcli to activate the WoL feature.

When putting the Steam Machine to Sleep (i.e. S3) i can wake it up via WoL Packets from my other machines. This also works fine after rebooting, so the settings are persisted.

When i shutdown the Steam Machine (i.e. S5) i cannot wake the machine anymore via Wake on LAN. I have read multiple reports of others having the exact same problem but also, that if they install Windows and activate WoL there, it also works from the S5 state, until they boot into SteamOS again.

So most probably the hardware of the Steam Machine is capable of utilizing S4/S5 for WoL but the SteamOS is maybe misbehaving or the ethernet module.

For now the only workaround is to just put the Machine to Sleep instead of Shutdown (wich i really don't like).

Steps for reproducing this issue:

1. Connect the Steam Machine via Ethernet
2. Enable S4/S5 Wake on LAN Support within Steam Machines BIOS
3. Boot and go into Desktop Mode
4. Enable WoL features via nmcli connection modify "Wired connection 1" 802-3-ethernet.wake-on-lan magic
5. Shutdown the Steam Machine
6. Try to wake the machine from another device in the same network via magic packet.

Reproduce the issue on a Steam Machine using the listed BIOS setting and the nmcli Wake-on-LAN command, then compare wake behavior from S3 and S5. Check the Ethernet Wake-on-LAN state before shutdown and verify that a magic packet wakes the machine from S5 without changing the working S3 behavior.