When I choose hibernate or shutdown from the power menu, it turns off everything, even the HDD spins down but the fan remains on (probably at the last speed it was on), the processor/GPU apparently is/are still powered as the fan exhaust remains hot, the power and WiFi/BT LEDs remain on. Battery status LED functions correctly (off: charged, RED: low, white: charging).
It remains in that state until I physically long press the power button to power it off or the battery totally drains if not on AC power. That may sometimes not happen if it was on battery power or if it has been plugged in only for a short time (15 minutes or so). It happens also if it was on battery power, I hibernate then close the lid before it completely turns off. Normal sleep works fine, may sometimes hang if I reopen the lid before it completely sleeps.
My power settings: sleep and hibernation enabled. Press power button does nothing on both battery and AC power. Closing lid on battery power will sleep and will do nothing on AC power. Hybrid sleep enabled.
It's a Dell Inspion 15R 3537 (i5, 12 GB RAM), running a genuine copy of Windows 10 Pro (build 17134.165, version 1803). Automatic updates enabled, bios version up to date from the official dell website, all drivers up to date.