Loosing connection when launching Utorrent client or Steam

Hi All,
I have small problem with my computer. Recently, when i launch certain applications like Utorrent client or even Steam, my computer looses connection. It is not problem on router because my laptop is still working and fine, when this problem occurs.

So i thought it might be the wireless card i have installed, so I bought another one, different type but this problem persists.

Does anyone know anything about this problem? I would really appreciate your help. I am running Vista.