If you have the option, try to borrow an AGP card from a friend. Usually when you get lines and misplaced artifacts, it means the card is dying. If you are overclocking it, try lowering it to stock speed. Also, it could be that the heatsink/fan is dying causing it to overheat. Take off your side panel, and turn on the comp. See if the fan is spinning.If its still under warranty, try to RMA it. I did it with my GeForce4 Ti4200, and got a better one than I sent in.