If your board won't turn on, technicians typically check these points in order: Is the SIO getting standby power?
signal back to the motherboard. Only after this do the voltage regulators (VRMs) for the RAM and CPU activate. Platform Reset (PLTRST): desktop motherboard power sequence pdf
line low (grounding the green wire on the 24-pin connector), which triggers the PSU to output 3.3V, 5V, and 12V rails. Power Good (PWROK): Once the PSU voltages are stable, it sends a Power Good If your board won't turn on, technicians typically
: Once voltages stabilize, the PSU sends a Power Good signal to the motherboard. If your board won't turn on