Normal behavior. Modern processors naturally have a very low internal resistance (often between 1Ω and 10Ω). Do not mistake this for a short circuit.
For real-world repairs, having the exact service manual for your laptop model is invaluable. These manuals provide official disassembly procedures, power flowcharts, and circuit diagrams. Popular sources include DIY laptop repair forums where users share these resources. Always remember to search for the specific board number (e.g., "Dell Latitude E6440 VAL90 LA-9931P") to find the correct schematic and boardview files. laptop motherboard chip level repair guide pdf
Always wear an anti-static wrist strap connected to a grounded point. Use a static-dissipative ESD mat on your workbench. Normal behavior
The entry point of the 19V rail uses two N-channel MOSFETs driven by a charging IC (e.g., ISL, BQ series). If the first or second MOSFET fails to open, the board will receive no power. For real-world repairs, having the exact service manual