I am installing an Xtasy GeForce4 Ti 4200 AGP card, but when the card is seated properly in the AGP slot, the top of the card is tilted so far inward that I cannot line up the holes in order to screw the card down. If I line up the holes and seat the ports correctly, I cannot push the card down far enough into the slot. Is it the card, the slot, or the motherboard?