Weird problem with a wireless card

[DoNoTincinerate]

My wireless card for my old web browsing latitude C Is starting to act up, as after i start the computer, i have somewhere around 1-2 1/2 hours of use, before my wireless card can no longer acces any network, and the times have started to go down every now and then
Here are some of my specs
The wireless card is old, only a wireless B
My computer is a dell Latitude C 540
It is running Ubuntu linux 8.04 Hardy Heron
Please help!

[GroundZero3]

Do you have any other clients using the wireless network?

[Big_Daddy]

That's usually the beginning of the end of a wireless card

[DoNoTincinerate]

Yeah, it seems to have subsided, I just changed my router because my other seimens POS wouldn't give my ps3 Nat type 2. I think it was that router,i hated that thing ever since I got it.