The first recommendation would be: stop trying to use power button to shut down your computer. If so, then two things must be at work here: 1) your power button is programmed to put your computer to sleep (instead of shutting it down), 2) your BIOS is configured to put your computer into shallow sleep state (S1), instead of deep sleep state (S3).
It is going into S1 sleep state.įrom your description, it sounds as if you are doing this by pressing the power button. Your computer is not shutting down at all.