I have some tips you may want to use OneBuck might not have touched on... Let's try a troubleshooting step check.
1. Check in your motherboard BIOS/UEFI settings if you have the Network Adapter enabled. Usually it will say options for Enabled/Disabled. If it is disabled, set it to enabled, save the settings, and reboot. If the network doesn't come up, proceed to step 2.
2. Check the network cabling. Make sure your network cable is a Cat5 or higher certified cable (I personally recommend no less than Cat5e cabling). Check for breaks in the cable, a broken clip on the plug, if the cable is plugged in, etc. If cable is damaged, try to replace it with a better cable. If network still doesn't work, proceed to step 3.
3. If the lspci utility does not list a network device, there is a chance the kernel driver was not enabled for that device or the card might be dead. lspci should list the device type, brand, model number, or make. If it doesn't, you might have a dead network chip. If it does come up, but no driver is loaded, you may need to rebuilt the kernel to support your device, if a built-in driver exists.
Follow these instructions here:
When building the kernel. I recommend you use the make menuconfig
to check the kernel registry for your device, and enable it. You can build it as a module (preferred method), or built into the kernel. If the new rebuilt kernel and modules do resolve the issue and load the driver, you're done.
If not, then you may want to contact your PC manufacturer for information about the network card, check for recalls, or even look into a USB Network Adapter, or look into an RMA if it is indeed a dead adapter.
Be advised that some Network Adapters may be a Staging Driver and could require loadable firmware. If you need help finding firmware, we can help you.
My advise is to work your way down the checklist and see what is going on before you get to step 3.