Registered an account to reply here. Managed to get 9.45 watts idle using 245K & Z890. MOBO: Maxsun Z890-A PSU: Thermaltake PF1 650 RAM: single stick of 16GB SSD: Kioxia SD10 The onboard LAN is disabled since RTL8125 is somehow unsavable. Switching to RTL8125B or I226V would not add much to the idle power. The screen and other peripherals are disconnected after running powertop --auto-tune. Thanks to @knotgerman for pointing out the importance of Low Power S0 Idle Capability. My board had the setting Password protection of Runtime Variables on by default, so I have to follow this guide to modify the default value of NVRAM and modify the rest settings using the traditionalsetup_var method. I don't find other new settings in Arrow Lake as useful. BTW, I don't think long idle numbers in Energy Star always reflect the actual idle power, in other words, I don't agree Modern Standby is an idle state instead of a sleeping state. Some tower models show extremely low long idle power usage, because they have Modern Standby enabled by default, thus they have Long Idle (watts) identical to Sleep Mode (watts). Dell seems to note their default low-power mode, so this model shows extremely low long idle power as a tower work station, while this one idles more reasonable at ~20watts. Since modern standby is useless on desktop, I'd say ~10watts is also what OEMs have achieved on tower systems, like this one.