Laptop With Slow Connection

Hello all, my first post here.

Here is the situation.

Bought an Apple Extreme Base Station, was using an Apple Express for my wireless. The Express worked brilliantly, just plugged it in and the computers saw it immediately and we had good speed and coverage.

We are renting several rooms to students and the room furthest away from the base station was not getting a strong enough signal and kept dropping the internet. Hence the base station upgrade.

Now one student is having problems. Super slow internet connection. Her signal strength is excellent and the speed is a consistent 56k. She had much better performance with the Airport Express even though the signal strength was lower.

This leaves me scratching my head. I helped her a bit by downloading and installing the latest drivers for her built in wireless adapter (intel 2200bg) and performance improved somewhat but I'm not sure whether it is a temporary thing. She has a Compaq Presario V4000 laptop running XP Home.

I have the base station set to channel 8 and we are running WPA2 encryption.

I turned off her Norton firewall and turned on Windows. (it seems that norton doesnt play well with the Apple.)

She uses the HP wireless assistant which I didnt have a chance to update.

I'm pretty much convinced its a hardware issue on her end since my laptop (a new HP running Vista) is further away from the base station and is blazing on the net.

Any insight as to what is going on would be appreciated

*added info*

I had to put a network bridge in place using the old Apple Express as the furthest client was still dropping out of the network, this solved that problem.