(Leave empty for random seed, 1–4096)
The complete power-on sequence from a cold start proceeds through the following stages. Most power sequence PDFs will follow this general order, though specific signals may vary by chipset generation and manufacturer.
— The master reset signal for the entire platform. After PWROK and VRMPWRGD are both high, the PCH drives PLTRST# high (inactive). Approximately 1 ms later, the CPU receives CPURST# and begins executing the BIOS/UEFI. desktop motherboard power sequence pdf
After all voltage rails have successfully stabilized, the VRM sends a PWRGD (Power Good) signal to the PCH/SIO. This indicates that all power required for operation is stable. 7. System Reset (SYS_PWROK & PLTRST) The complete power-on sequence from a cold start
: Acts as the gatekeeper of the power-on signal. After PWROK and VRMPWRGD are both high, the
+5VSB |--------------------| (always on) PS_ON# |____________________| (low pulse) +12V | |--------| PWR_OK | |-----| VDD_SPD | |---| DRAM_VDD | |--| VCORE_EN | |--| VCORE | |-| VRM_GD | |-| PLTRST# | |---|
This sequence applies to most modern desktop motherboards (Intel and AMD). Stage 1: Pre-Power (Standby Phase) Power Supply (PSU) plugged in, switch turned ON.
As soon as the PSU is plugged in and switched on, the system enters a standby state.