Vista Laptop knocking all other computers off line

I have a wireless linksys router wrt110. I am running a vista desktop (that is hooked through a cable), an xp laptop (wi-fi), and an xp desktop (through wireless adapter). That system works great.

But I also have a compaq cq-50 running vista, and when I turn it on, it will not connect to the internet and it knocks all the other computers off line. The only way to get them online is to turn off the compaq, and reset my modems (the linksys and cable modem).......(sometimes it will run fine, along with the other computers, and it will just quit all of a sudden).

I have tried to find a solution, and the only thing I could find is the broadcast flag in vista. It is recommended to fix it in registry, but I am unsure of which {GUID} item I am suppose to fix. And I cannot find directions on finding out which one I need to modify.


I am thinking of downgrading to xp on the compaq. Would that help my problem?