To test the Killer Xeno Pro, we installed it in an AMD Phenom II X2 550 based system running Windows Vista Ultimate, with 4GB of RAM, built around the Asus M4A79T Deluxe motherboard. The M4A79T Deluxe features an integrated Realtek RTL8112 gigabit network controller, which we used for comparisons to the Killer Xeno Pro. The rest of our network configuration consisted of a D-Link DGX-2208 gigabit switch, connected to a D-Link DGL-4500 router, which was in turn connected to a Motorola cable modem.
For our in-game tests, we played an on-line game for five minutes and recorded the framerate with FRAPS. Each minute, we also recorded the ping time reported by the games. It is difficult to exactly duplicate game tests taking place over the internet, but we made every effort to ensure the test runs were as similar as possible--we used the same servers, on the same map, with the same numbers of players / bots. The only thing that changed was the NIC we used to connect to the web...
In both our Left 4 Dead and UT3 framerate tests, the Killer Xeno Pro offered slightly higher average framerates, but markedly higher minimum framerates. The differences can most likely be attributed to the Killer NIC's ability to offload network operation from the host CPU, freeing it up to handle other things.
Ping times were also lower on the Killer Xeno Pro, virtually across the board in both games. The differences weren't huge, but the Xeno Pro definitely offered improved pings over the integrated network solution.