Wireless suddenly slow, but only on one PC

Hi all,

O/S = XP Pro SP2
Router = Linksys WRT54GL Standard Firmware
Card = Linksys WMP54G

In the last few days, my internet connection has been excruciatingly slow
from my PC. It has completely randomly occurred, as I have not made any
changes to the system.

I have tested the speed using my Laptop that has a built-in Intel 2200BG
Wireless Card, and this is speedy as usual. I've un-installed and
re-installed the drivers for the card on the PC with the latest drivers, but
this has not helped.

Can anyone shed any light on what it could be?

Thanks,

Mike