Symptom: The laptop turns on, the Caps Lock key lights up, but the screen stays black. An external monitor via VGA or HDMI works perfectly. This indicates a discrete GPU failure (UMA models won't have this).
Without BoardView: You might reflow the AMD GPU (wasting time). With BoardView: hp probook 4540s boardview
# Initialize viewer
viewer = HPProBook4540sBoardViewer("hp_probook_4540s.brd")
To view the boardview file, specific diagnostic software is required. The files cannot be opened with standard text editors or image viewers. Symptom: The laptop turns on, the Caps Lock
fig = viewer.renderer.render_layer('top', highlight=['PU3', 'U5'])
plt.show() Symptom: The laptop turns on