Vertical Bar on Screen

Basically, a few weeks ago, the picture on my laptop started corrupting and then it stopped booting at all.  We ran various diagnostics and ended up replacing the video card and the hard drive.  Everything was working fine for a few days after these were installed and then all of a sudden a black vertical bar, about 1.5 inches thick, appeared in the middle of the screen.  We ran the PSA diagnostics and received a 3-3-3 error code.  We also ran the BIST screen test and the bar remained during the test.  The bar was black at first but will slowly lighten to white at times (and vice versa).  Also, we plugged the laptop up to an external monitor and while the black bar appeared on the laptop screen, it was not seen on the external monitor.  Essentially I'm asking if there is something I'm not doing, or if I should just go ahead and replace the lcd.  Any comments will be appreciated, thank you.