Code 43? Drivers Help Please

Im using a vostro 1400 that I bought last august. A few days ago, my screen turned funky colors and froze up, so I shut it down and turned it back on a minute later. However, then my screen stayed black except for some lines. At first i thought it was something with my screen, but eventually I hooked it up to a monitor and found out in the device manager that my driver had found problems and it said "Windows has stopped this device because it has reported problems (Code 43)".
Therefore, i uninstalled my old drivers, then installed the 169.09 one. After that it was fine. However next day it happened again, and i repeated the process again.
The process has been going on for a few days now and I have since installed the 174.74 drivers. Im really confused on whats happening. Anybody know whats wrong? Thanks in advance. Sorry if im not clear on whats happening.

Btw my gfx card is a 8400gs

 

My guess is a failing GPU/motherboard. Hopefully you're under warranty.

 

If the external monitor works ok, then I'd guess you may have a loose connection between the video card and the LCD. That's just a guess though.

In any case, you should have gotten at least a 1-year warranty, so make Dell repair it before your warranty runs out.

 

Thanks for the help hep and swarmer. I've called Dell and they said they would send someone to replace the LCD, but i kinda doubt that its gonna fix the problem, but i'll see. Anyone else have any ideas?