Integrated network controller just vanished, like nothing was even there.

This is an HP DC-5800 that I use for server stuff like Minecraft and my website. It runs Ubuntu 18.04 LTS minimal install. Tonight I unplugged everything in my room for half an hour or so because of a lightning strike that was way too close for comfort, I shutdown the computer properly. I took this opportunity to dust it out and harvest the optical drive in case I need one in the future. I got it back up on it's shelf and booted. Surprise, I have no network connection. I tested everything between it and the modem and it all checks out. I tried multiple cables. I noticed the lights around the ethernet port weren't on at all like they usually are. I went digging through the bios and even reset it, nothing. I went to the internet for a solution and found I could check on the network hardware with # lshw -c network, which that command returned nothing at all, like ls in an empty directory. I booted an Ubuntu live USB and it behaves the exact same, also there's no ethernet connection in the GUI settings. The only explanation I can think of is the lightning from earlier tonight, but it would have to go through a modem, router, and reach the the computer without damaging anything other than that computer. Not sure if it's important, but none of the outlets on that side of the room are grounded. The outlets where my main workstation is are grounded.