This command should help.
lspci | grep -i ethernet
You should run it for 5 complete passes, or longer.
The Ultimate Boot CD (UBCD) contains Prime95, MemTest86+ and a lot more. Do a search on the internet for it. Be very careful what you click on. There are a ton of adds which support the project, but I just hate all those ads and they trick you with the word “Download”. It is there to download, then you can burn the ISO to a Flash drive.
As for HexOS, I’m not sure about troubleshooting it. HexOS should support the current version of TrueNAS scale, it’s been out for quite a while, but you will need to check into that.