Cabled connection cuts wireless, help pls

[Vember]

Hi all, i have been working on this for some time now and have been bearing with it... but it is time.

I have a "network" of three computers on a 4port + wireless router, dsl connected to it from dsl modem.
2 computers are connected to the net via wireless and the third is giving the problems

>> Every time i connect the cabled connection it cuts off the internet to the other computers. >> the radio signal is still connected but the computers with wireless cant access the net but the cabled had not problems with it.

What is up??

All ip addresses are Auto obtained but dns is manual

let me know if any other info is needed, all help is appreciated

 

[Vember]

any suggestions??

 

[gregmcc]

From the 2 wireless machines can you ping the router when their connection dies.