I have been troubleshooting this for a long time, posting here my solution so that it may save somebody else some time.
TL;DR:
If your PC won’t wake from hibernation (S4) via USB devices or power button, but resumes once force-powered, check this BIOS setting:
Disable: USB Power Delivery in Soft Off (S5)
(Located under: Advanced > Onboard Devices Configuration)
This resolved the issue on a ROG Z790 system. Hibernation now works with USB wake as expected. Fast Boot was not the culprit
I ran into an issue where my ROG-based system (Asus ROG STRIX Z790 A GAMING WIFI to be precise) would enter hibernation (S4) just fine using shutdown /h, but would not wake up:
USB devices (keyboard/mouse) did not wake the system despite being wake_armed
The power button also did nothing unless held for ~5 seconds (forced power cycle)
After forcibly restarting, the system resumed from hibernation — confirming that the session was preserved and hibernation worked
Symptoms and Observations:
powercfg /a confirmed S3 and Hibernation (S4) available
Devices like HID keyboard/mouse and LAN adapter were correctly armed with powercfg /devicequery wake_armed
Wake capabilities confirmed using:
Fast Startup (Windows) was disabled
Fast Boot (UEFI BIOS) was enabled, and not the cause
Resolution — USB Power Delivery in S5
After exhausting OS-level checks, the fix came from a BIOS setting:
Disabling “USB Power Delivery in Soft Off (S5)”
BIOS Path:
Advanced > Onboard Devices Configuration > USB Power Delivery in Soft Off (S5)
Explanation:
This is completely counter-intuitive - you would think that this setting would be needed to power-on USB devices in sleep mode - but here it seems to interferes with S4 wake behavior, likely due to USB controller behavior at the ACPI layer (or said ChatGPT when I tried to understand - but I still don't).
Disabling it allowed USB wake to function as expected from S4.
