ATX Power Bracket ATX Power Switch: System power (on/off/standby) controlled by momentary switch attached to the motherboards 2 pin power switch header. Reset Switch:Reboots PC without powering system off, attached to the motherboard's 2 pin reset switch header. (either switch in this kit can be used) System Power LED (green):3 pin connector lights when power is ON. Blinks when system is in standby or sleep. Spare 2 pin Power LED connector included! Hard Drive Activity LED (red):2 pin connector. Blinks with hard drive activity. See your motherboard manual for pin locations and panel functions.