It would be best to supply the missing details about the machine. But give these clues I would first clean the insides of the machine and leave the case cover off to sniff out if there is a heat issue as well as letting me check if all the little fans are working.
My guess is the video card is failing but I don't have all the details so it may be a bad guess.
Bob
Windows Vista Service Pack 2 T6400 2.00 Gmz
I installed the Sims 3 on my dell computer. Everything was working fine until the frequent computer freezes. My screen will be covered in broken white or green lines, and I can't start it. so i have to manually turn my pc off and on again. I stop playing the Sims 3 game for a while. The thing is that it is not the Sims 3 game. This morning I was listening to a song on the ITunes storeon my laptop and it happen again!! A beeping sound and the plaid lines all over my screen. I am not sure how to describe this problem. Is it my graphic card? I did a complete system restore and nothing helps.

Chowhound
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