Strange Problem of XPS M1530

Hi Giys,
i have left my laptop on for couple of hours. once i came back and started using it i have experienced a weird problem. my whole desktop started blinking with different colours of small drops. as much i use as much they increased and finally i couldn't see anything. then i restated machinee by pressing the power button. but i didn't get any problem notification. and also i had my third party screen saver installed. is their any1 experienced this sort of problem. my machine is 7months old but mother board has been changed couple of months ago. plz help me guys. i m in tense.

 

Probably that 8600M GT kicking the bucket? Do the artifacts show up on an external display as well? If they do, it probably means you're going to have to get a new GPU...

 

what do u mean by artifacts show up?
don't u think it is because of nvidia driver. cuz the one i was using was downloaded from nvidia website which was whql. i have changed back to it the default one from dell website. or the bcz of the pirate screen saver. i should have seen screen saver, but when i came to computer there was no screen saver running.

 

Those are the artifacts. I'm asking if they also show up on an external display.

 

sorry for my ignorance man. actually it has just happened only once. what do think about the nVidia driver? and also i can see that my windows sidebar's notepad direction(Arrows) buttons and autoshutdown buttons r not showing up. how can i repair them? they used to work fine b4 this artifacts.