Does the system have a firewall enabled that is blocking the traffic?
Did the dig result actually return an ip address for the dns query you tried?
Are you able to ping things on the internet from the terminal by IP and hostname (i.e. 8.8.8.8 and google.com)?
If you're using a desktop, there's no compatibility worries for motherboard and gpu. They all use PCI-e ports and are standard.