I power off the Restore on AC/Power loss on bios c

Depending on your motherboard, does the MB itself have surface-mounted power button? If not, you can touch the power button pin-header on the MB with a screwdriver which shorts the pins and the system will power on just as if you've pressed the power button on the case.

Normally, if you've been manually turning your power supply on on and off via the switch on the power supply itself, then it sounds like your case button has not been wired correctly or to the correct pins on the motherboard. Like you've accidentally connect the power button to the reset pins, and the reset pins to the power button, etc.

The feature you're describing (Restore on AC Power) is usually there for one purpose - to auto-power on a computer after a power loss. Like the PC is on and running, the power at your house goes out for 30 mins, and when the power is restored to your home, the PC will automatically come back on. The purpose here is so the PC will auto-start after the power failure, meaning that if you're out of town for a week, and you lose power at home, the PC will come back on when the power is restored. Thus you don't have a PC that sits off for a week until someone goes there and presses the power button on the case.

Using this feature to normally turn your PC on and off is not what the feature was designed for and your description sounds like this is what you're using this feature for.

Very good! So it sounds like your power button on the computer case is not wired correctly.