Ahhh… apologies! I replied but I should have noticed first to whom I was replying to. Of course you knew already about the ECO mode. Sorry! 🤦 Anyway, there are a lot of BIOS/UEFI options (afaik mostly undocumented), some are for the USB, WLAN, Bluetooth but I’m not sure any of them will cut their power.
Anyway, you can always open the case and physicaly remove/disconnect the Mediatek MT7925 Wireless/Bluetooth Card to fully disable it. And the speakers. But realistically and IMO, that shouldn’t be necessary and defeats the purpose, this APU mini PC is already a little Power consumption marvel, on idle the APU consumes only about 5W and the whole mini PC about 16W. Still the APU can be pushed up to 140W on-demand and the whole mini PC at about 180-200W depending on the load/connected peripherals, and all of this with a small compact built-in 230W rated power supply (no need for an external adaptor).
What more can we ask for? Honestly at this point I only need that the Linux amdgpu driver Pageflip freezes gets sorted or workarounded (not related to Beelink) and that the Intel LAN ports stability gets resolved (although I haven’t experienced it myself).