Question : Problem: Laptop Crash _ Seems to be a VIDEO Card problem

My computer is :
DELL XPS M1710
Nvidia Geforce Go 7900 GS (Driver recently upgraded from Dell_ 2 weeks ago)
17" screen
2.13 Ghz Core 2 Duo processor
2 gigs Ram
80 gigs HD
Windows XP Pro SP2
Dual Monitors (the laptop and a extra one 19" from Dell also)

Hi, just 30 minutes ago i was using my computer, and suddenly The second Monitor (19 ") went completely black, ( " AS " when it is ON and connected to the laptop, but with the Dual monitor option turned off...(meaning, is not like it was disconnected) )
Then on the laptop monitor, everything stopped, the mouse moved but like after 10 seconds after i physically move it... So it was NOT COMPLETELY freezed, because the mouse moved a little bit, but i was unable to do anything else, not even shut it down by the start menu.  3 minutes after this happened, the laptop monitor also went black, but the computer was still on...  So I shut it down pressing the ON button for 10 seconds.

I restarted it, several times, and everytime, it starts and i See the DELL Logo and XP logos but with a lot of vertical Lines, then it goes to just a lot of Horizontal messed up lines, and then Completely to black as soon as the OS starts to load...

2 weeks ago i had a video driver problem which was causing the computer to use a lot of resources, so i unisntalled it and downloaded the latest nvidia driver from Dell webpage.  Since then everything wasa perfect uintil Today.

Also, something that has been happing not on a regular basis, but once a while since several months ago, is that the Second monitor goes Black for a moment, say 3 seconds, and then comes back. I tought it was the electric cable which was a little bit loose, but, now i am starting to think it was not the cable.

So, I will call DeLL because the computer is still under Warranty, but i will appreciate  a lot any help you can give me to understand this problem or its cause, becuase thats wwhat i want to do, understand it. I know Dell will probably fix it, but knowing a little bit a bout the subject will be very good for me. If something like this happens again to me, and i have no warranty, i will like to have some experience on the subject to be able to take good action.

Thanks

Answer : Problem: Laptop Crash _ Seems to be a VIDEO Card problem

vertical lines are usually a sign for a dying or already dead video card.
this could happen because of water on the mainboard, too much heat, a short circuit or simply a heavy vibration or a heavy shock.

since you got warranty i would avoid trying to fix it yourself, you might loose your warranty.