One card was from a friend, and was removed working when he upgraded his video card. The other was bought new from NewEgg. The reason I think both cards are good, is that both stop working at the exact same spot. About one second after the Window XP Pro welcome window apears the computer locks up. No keyboard, no mouse no nothing!. The computer also freezes going into Save Mode. The only fix is to remove the HD3870 board and install the the old video card.
thanks for your reply