CARD NET on Laptop

I have a laptop XP..The connection to the lan stay , approx...2-3 minute and after that the link has broken.
I changed different speed for net card , 100 mb,10 mb..Same situation...Is probably the net card ???

 

I think more information is needed, there are plenty of things that could interfere with your network connection.

What's the signal strength?
How far from the base unit?
How many others on the wireless network?
How many other wireless networks nearby?
If there are any other networks are they using the same frequency?
and finally, are you using any other wireless devices, keyboard, mouse, cordless phone (near either the Laptop or the router) etc?