Okay, that puppy is a
Cooler Master Centurion 5 II mid-tower case. Your buttons from right to left are power button (the large one), reset button and front fan on/off for your blue LED 120mm front fan.
And that's a mystery. Why would you NOT want your front fan to be on all the time?
Or why would you not use a 3-wire fan and let the motherboard control the throttle according to component temps?