If it has an internet port for a ethernet cable plug it into the box and into the back of the PS3. If it is supposed to be WiFi then use you PS3 to search for the signal and then use auto to...
Not all U-verse plans support gaming and do not even come with internet unless you have paid extra. Your PS3 is designed to seek a WiFi signal and auto connect when you use the ps3 networking...
With a cross-over cable just plug one end into the laptop and other end into the PC using the RJ-45 jacks. Then, configure both with static IP addresses and you are ready to go.
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