dual monitor problems

i am trying to get xp running with 2 graphics cards and monitors. i can get the first card up and running fine and activate the second to a black screen. then the fun starts. as soon as i click expand my desktop onto the second monitor it puts the wallpaper up but no taskbar as you would expect but shuts down the first display at the same time. if i force the second card to expand and be primary monitor it puts up wallpaper and taskbar but still shuts down the first display. i can then expand the screen back onto the first display and make it primary display and it will work till i shut down or change display settings then i loose the first screen again and the taskbar and have to start in safe mode and disable the second card and go through it all again. does anyone have any ideas that may help. sorry about the long post but this is driving me nuts.