everything was working fine but one fine day when i switched on my alienware 17 it started with 8 beeps and nothing to display. I connected to the external tv, on tv was working fine. I called dell tech support, they advised me to replace my lcd screen, They sent a engineer to home, the engineer started removing one part by one part to isolate the issue with first ram then graphics card then motherboard. he listened to the corresponding beeps. it seemed everything was fine. Finally he put everything back to check the old screen, the old screen switched on with back light and everything. but there is a static and lines. he checked it with the new screen still there was static. So we figured its not the screen problem. 

I Plugged into external tv and have updated the bios display drivers and i ran the BIST test on the lcd.  can see all the colours clearly no static or distortion.

The static comes immediately upon switching on.

what might be the problem?