Abstract: Described is a personal computer system which includes a central processing unit (CPU) and power management circuitry (PMC) in circuit communication with the CPU. A power supply is in circuit communication with the CPU and the PMC and includes circuitry for selectively providing system power to the computer system and auxiliary power to the PMC (1) from an external source or (2) from an internal source. When the system is in a normal operating state and the external source stops providing power at a predetermined level (e.g., brownout or blackout) to the power supply, the power supply is operative to generate a control signal to the PMC and switch to its internal power source. The power management circuitry is characterized in that while in the normal operating state, responsive to the power supply activating the control signal, the PMC causes the computer system to change to the suspend state wherein the entire state of the system is safely saved to a non-volatile storage device.