Hello
As a result of my graphics chip exploding in a screen of green i have discovered that if you change the power setting from "Balanced" to "High Performance" it cures the problem, no green lines. Problem solved. I hope.
As this AR21S is only 30 months old and has been looked after, frequently cleaned, and has always sat on a desk, i was a little miffed when he NVIDIA graphics chip started playing up.
Hopefully i can keep it going for a little bit longer before sony forces me to buy a Apple's 17" Macbook Pro.
For the moment i am a happy sony vaio user.