I've had this problem in the past. You might look at your NIC settings on your XP machine. Specifically, you might be set to Full duplex when you need to be set to half. For short bursts, Full duplex on a hub will work ok, but long transfers will be bad. Look for collisions on your network hub. If you see the collision light on a lot then try setting your NIC to half duplex and see if that works better. You'll usually find that setting in the "advanced" settings.