HDMI / Ethernet Problems after Lightning Strike

[Tom2018]

Hi All

I was working on my HP ProBook 4740s Notebook PC when lightning struck nearby yesterday. I heard a zap coming from one of my electronic gadgets right at the time the lighting struck. Not sure whether it came from my surge protected power board (being tripped) or from my laptop/modem/external monitor. Since then, the ethernet connection from my modem to the my 4740s is no longer working, while the WiFi function of the modem still gives me access to the internet. Also, since the "zap" my external Dell monitor (connected by HDMI cable, is no longer displaying what's on the laptop screen. Ethernet & HDMI ports on my 4740s are right next to each other. The 2 USB ports next to the HDMI port still function properly. I have also tried another modem, but the ethernet cable does not respond there either; so it appears that the fault would lie within the laptop (ie, that the latter is not responding to the modems).

I have run a number of HP diagnostics tools (the DOS based "f2" during startup & the "HP PC Hardware Diagnostics Windows" program) and also gone through the "Maintenance & Service Guide" for the 4740s to identify which of the diagnostics covers the HDMI & Ethernet ports. It appears that none of the diagnostics tools covers the "System Board" (which per the maintenance manual includes the ports in question).

I would greatly appreciate your feedback on how to go about rectifying the above issues. That is, whether I would have to replace the "System Board" or whether there's any other tricks to get the monitor and the modem to "talk" to the 4740s again. Many thanks in advance.