I just changed my video card.  When I booted the computer up it posted went to the opening XP screen.  Heard the sign-on music but then no video.  I then replaced the video card with the old video card that was working.  I rebooted the compter it posted  and the XP window satrted to open I heard the start up music and then no video again just black screen.

Any one Know what the problem might be.

Thanks

   It sounds like you have the wrong drivers for the video card.  I would suggest that you call the video card manufacturer and let them help you get it going.