(often identified as a manufactured board) is a proprietary motherboard commonly found in business-class desktops like the HP ProDesk 600 G2
- VCC_RTC (Real-time clock backup voltage)
- +3V_DUAL (Standby power)
- VCC_CORE (CPU core voltage, typically 1.1–1.4V)
- 32.768kHz Crystal: If this crystal is not oscillating, the EC cannot function, and the board will not turn on.
- ACIN Signal: Does the EC know the charger is plugged in?