Depending on what the problem was, it may be that the video card was fine, but the LCD controller was faulty.
It could be that a cable was damaged, but the all-white display usually points to the matrix controller being faulty - meaning a new board is in order - call back and have it repaired again.
I had a 3 years old Inspiron 8000. ATI Mobility video card, out of warranty, and a wonderful black screen on my LCD all the time.
The LCD screen remains almost completely blank after the dell logo all the way to the loading of windows... the screen is very, very faint with only the outlines of shapes showing up.
I installed the latest video driver (ATI for xp) and BIOS driver both from DELL site. Also connected the laptop to an external monitor (working fine so there's no problem with the videocard).
When I press Fn+F8 to toggle crt/lcd the laptop attempts to light up the lcd for a few seconds (quite orange light), but then goes back to blank.
The backlight and/or inverter need replacement - under $50 in parts, perhaps $100 in labor - any competent computer repair shop can do the replacement.
I am having some display problem with my Dell Inspiron 8200. There is no display when I turn off my computer and restart it again. However, computer works fine if I connect it to an external monitor (using <fn>+<F8> keys). After series of On and Off trial to get the display on my laptop monitor, the display does come up however with very low screen resolution. I generally reset the resolution back to my original preference and the display works fine for a while, however then it shows that the file called NV4_disp has a caused a problem and computer will be turned off in order to prevent damage to computer. I restart the display and it goes blank again till I hook up with external monitor and keep trying On and Off. I am tired of this routine and thought let me get some help from dell forum. So here I am...