Now that power is stable, the digital logic must be synchronized and reset.
The SIO chip releases the Resume Reset signal to the PCH, indicating standby voltages are stable. Phase 2: Power-On Trigger (S5 to S0) desktop motherboard power sequence pdf exclusive
The Super I/O pulls the PSU's Green wire to Ground. This tells the PSU to turn on all main voltage rails (+12V, +5V, +3.3V). Phase 3: The Power-OK Logic Now that power is stable, the digital logic
The moment the PSU is plugged in and the main switch (if present) is on, the rail goes active. This powers: This tells the PSU to turn on all
This guide to the is a comprehensive resource for technicians and hardware enthusiasts aiming to master component-level repair. Available as a detailed PDF, it provides an "exclusive" deep dive into the precise timing and signal order required for a motherboard to transition from standby to a full boot state. Core Power Sequence Stages