Looking for Network Adapter

Solution
That is not accurate. Right from the Gigabyte specifications page -- Qualcomm® Atheros Killer E2201 LAN chip (10/100/1000 Mbit) So either you have a cable issue, or a configuration issue, or possibly a driver issue.
Cable is the simplest thing to test. Swap the cable to a brand new cat6 cable.
That is not accurate. Right from the Gigabyte specifications page -- Qualcomm® Atheros Killer E2201 LAN chip (10/100/1000 Mbit) So either you have a cable issue, or a configuration issue, or possibly a driver issue.
Cable is the simplest thing to test. Swap the cable to a brand new cat6 cable.
 
Solution
Cables are very strange sometimes. They can work on some machine and not on others. It costs almost nothing to try another cable first.

You can get another nic card but it would be rare for the onboard one to fail. Maybe it is the stupid killer network drivers doing this. Try to install the killer drivers from their site that have all the killer features removed.