MacBook pro will not boot up?

My 2007 MacBook pro will not boot up. Sometimes just stops booting before password screen, but other times after that. If I get to put in my password it goes on, but I either get a blank screen or partial jumbled screen. When using boot disc and run hardware test it gives a video controller error 4VDC/1/40000003. Would that make it hang up and not fully boot? I can understand it giving blank and jumbled screens.