I was given an old Dell laptop by a friend which worked pretty well on my wireless network until recently. The signal was generally strong but is now very weak unless I move the laptop close to the router. I've tried pulling the WPC54G card from the computer and reinstalling it and found that the exposed plastic top is broken and can be removed from the card exposing the metal frame below. The plastic top was broken before I received the laptop.
What could be the reason for the sudden drop in signal strength? Could it be a software problem or is is more likely to be related to the broken plastic top?