Expose `Disable All Power Save` option (PC)

[helmesjo]

Your system information

• Steam client version: 174743473
• SteamOS version: 3.7.6
• Opted into Steam client beta?: Yes (preview, but tried all)
• Opted into SteamOS beta?: Yes
• Have you checked for updates in Settings > System?: Yes

Please describe your issue in as much detail as possible:

Describe what you expected should happen and what did happen.

Steps for reproducing this issue:

1. Install SteamOS on custom PC as per the instructions.
2. Connect TV monitor (Sony Bravia in my case) for Video+Audio (HDMI).
3. ~~Connect soundbar to HDMI ARC.~~ - Realised the issue persists even with soundbar disconnected.

There are numerous issues related to different power saving modes (sleep mode, bluetooth wake up, pulse audio), and one of the first things I had to fiddle around in the terminal with was to get "bluetooth wake-up" to work (it used the wrong sleep mode, had to create a custom systemd service to correct it on each reboot).

Besides flaky video output (sporadic lines/artifacts flickering very randomly), the latest issue I'm having is that the audio keeps dropping in and out, same as described here though so far the suggestions haven't helped.

Given that I'm running SteamOS on a PC there is no need for a single power saving feature to be enabled, I want to disable them all. Enabling Developer Mode only exposes the "WiFi Power Saving" option (which is disabled).

Request: Just expose all. Or better yet, expose a Disable All Power Saving and be done with it.

This is much needed, so thanks in advance! :)