WTF! Where did all this lag come from?

Ok I just recently received my repaired 360 after a 3 red light issue on Friday. The console was working perfectly fine and I didn't encounter any problems. I hop on Gears the next day (yesturday) and now I'm getting a bunch of lag:

1. When I search for games the connection for each room is red.
2. I get a ton of bullet lag (not the normal Gears of War bullet lag; this is more than a full second on every shot)
3. I cant accept game invites or chat invites from people I have before in the past.

I've unhooked my router and modem several times and also unplugged my 360 and restarted everything and I'm still getting lag. The computers in my house seem to be working just fine. I have RoadRunner Cable and I'm using a Linksys WRT54GX4 router. My 360 is connected directly to it.

Have you tried connecting the Xbox 360 directly to the modem, as opposed to the router?

Not exactly sure what the problem is (could be a ton of things), but you have to start with the basics.

There's no point in doing that because everyone in my house uses the internet. Does anyone know if Firewalls can be the problem or if they cause lag?theoryc2

It wouldn't be a permanent solution, just a test. Plus, if your old Xbox 360 worked just fine, there really shouldn't be issues with firewalls and router configurations - since you most likely didn't change anything while it was being repaired.

Perhaps you forgot to set the static IP again (assuming you assigned one w/ your old one)?

Well I just used the term "repair" because that's what the whole process is called. It's actually a new 360 system (has a different serial number and an HDMI port unlike my older model). theoryc2

I fully realized that - and it really has nothing to do with what I mentioned. An Xbox 360 is an Xbox 360, so unless you drastically altered your router settings during that time of absence, it should work identically to the old one.

Anyway, do the Network Tests (in the Dashboard) and see what it says.

EDIT: You really should have tried other games as well, perhaps Halo 3 or CoD4 (something with a matchmaking system). Using Gears of War as an online-game test is probably the dumbest thing one can do. So, next time try a few more options before you create a post.