Your T3 should be capable of about 45 Mbps. I'm assuming the EVGA Ethernet connection is at least 100Mbps<?> or even a 1000 Mbps. If so, adding another Ethernet port (using teaming) won't likely improve your throughput, as the T3 becomes the bottleneck. Though you might be able to see some % CPU utilization reduction by using the Intel CT Desktop adapter as there are many types of TCP/IP and checksum offloading that that are built into that card.
Here's a link to our performance page. While most of it may not apply, there are some things in it that could help. Take a look here: http://www.intel.com/support/network/sb/CS-025829.htm
As much as I would like you to buy an Intel(R) Gigabit CT Desktop Adapter, if your CPU isn't pegged, then adding the Intel Network Adapter isn't likely to improve with video streaming or games.
I hope that helps,
Intel - Wired Networking
Product Support Engineer