System Overview 1-33
When AC is applied to the system, Vaux (auxiliary voltage) is asserted and is sensed
by the PCM section of the motherboard if the On-Off Button is On. The PCM
asserts DC_ENABLE_L starting the power supplies. If there is a hard fault on
power-up, the power supplies shut down immediately; otherwise, the power system
powers up and remains up until the system is shut off or the PCM senses a fault. If a
power fault is sensed, the signal SHUTDOWN is asserted after a 30 second delay.
Cycling the On-Off button can restore the power.
