Tantalum or multilayer ceramic capacitors (MLCC) near high-heat zones frequently short to ground. Sourcing the HP ProBook 4520s Boardview and Schematic
Use the boardview to trace every single decoupling capacitor connected to that specific shorted rail. You can then use the "alcohol evaporation" or "thermal camera" injection method to see which specific component heats up and needs replacement. Core Component Reference Guide hp probook 4520s boardview
USB / I/O area