Display problems after connecting USB drive

One day when I have plugged my usb drive (with an indoor antenna), I saw appear on my screen a sort of blue cloud blocked my pc and since I have nothing but problems.

I restarted my computer and see a black screen appear to be color gradually, the picture remains static, this scenario repeats itself after a dozen start-up, always the same thing and after a dozen reboots restarts windows normally, but after a while I see the blue cloud, the pc crashes and restarts itself, but after reboot I still see this screen which is black in color and gradually I need me to do a dozen windows reloading so that starts but the blue cloud reappears after some time. I'm completely lost.

My config:

Dell XPS M1330, 13.3 "
Intel Core 2 Duo T7500
RAM 3072 MB
Hard Drive 250 GB
Screen 13.3'' WXGA TFT TrueLife
Resolution 1280 x 800 pixels
NVIDIA GeForce 8400M GS 128 MB

Have you arrived the same when you boot up your windows to backup to another hdd, then you reinstall Windows. If you still have the same problems is that your graphics card is almost dead.

I would also say that the graphics card to a problem, but if you can test see if the screen is not dead (you never know!). Test the graphics card on another config, or replace the graphics card of a pc problem for another.

I do not think the screen is dead because normally when I surf windows starts normally, but I will still do the test which is to connect my laptop to another screen tomorrow.

By against I do not know how to access the graphics card, I can do this on a pc manip fixed but not on a laptop.