It's pretty simple. You need to create a network bridge between your wifi and ethernet port on the laptop.
On laptop: 1. Bridge connections (wifi + ethernet)
On Xbox: 1. Manual ip address ie 192.168.1.xxx
2. manual subnet 255.255.255.0
3. Gateway = router's ip address
4. DNS = router's ip address
On router: forward link broadcast and data ports (TCP and UDP) to the manual ip address you gave your xbox.
Done.
- soulwarrior
Thanks a lot for ruining a thread.
On Gears of War 3 menu, press Back, then select System Link.
Then you select the mode you want and you wait until there's a game you can join.