packard bell media center.there have been no changes or new installations. operating system vista home , problem , im having problems with startup, turn on power get hp logo, the picture is overlaping with black vertical lines. new window ,goes to startup repair, error message, cannot repair this computer automaticlly. new window. system restore, error message unable to restore. the screen is still showing picture overlaping, with six mouse pointers, three top, three bottom of screen. unable to run safe mode, have done recovery with back up discs no change ,think hard drive is ok.