Did you install drivers for it? If so, uninstall them and reboot and see if XP can handle it with built in drivers. Also, check their website to see if it is compatible with XP and if so, see if there are any newer XP drivers for it. Better yet, call them. There should be a tech support number you can call on the website. When you spend that much on a piece of equipment, tell them that this performance is unacceptable. They will help you.