Macbook Pro 17inch (late 2008) display problem

Hello,

I have a display problem with my Macbook Pro 17inch running on NVIDIA 8600M GT graphic cards.

The whole display screen pops up with vertical lines which makes the display colour faded and sometimes changes to colour yellow or red.

I tried with display reset by pressing Shift + Ctrl + Eject to solve this problem but it still happen.

So which is the problem, the graphic display (NVIDIA 8600M GT graphic card or my display screen?

Thanks