I have a Dell Inspiron 6400 laptop, running XP SP3. The laptop has an internal wireless card, a Dell 1390 WLAN mini-card, which I use to connect to both my home and office networks.
Until recently the connection worked fine, generally showing a connection speed of 54 Mbps. However recently this has slowed to a crawl; at home generally to no more than 1 Mbps (which won't even allow me to connect to the internet), and at work to a maximum of 5.5 Mbps. This is the case even if I'm close to the router and the signal strength is reported as 'excellent'. Other machines connect wirelessly to both networks without a problem.
I've tried downloading the latest driver for the card from the Dell site, uninstalling it, and reinstalling it with the new driver, but this hasn't helped.
Is there anything else I could try which might help, or should I just assume it's a hardware failure and get a new wireless card? And, if the latter, is it feasible to replace an internal wireless card on a laptop, or should I go for a USB or PCMCIA one?