Dell Inspiron 1300 - bad screen - where to start?

I have a user who recently turned in an Inspiron 1300 with a screen problem. Unfortunately this machine is out of warranty, and the extended warranty we usually purchase was never bought for this machine (this is why users don't get to do their own ordering anymore!)

Anyhow, the screen is non-functional - it gives colored lines across the display from boot up (ie, no POST is visible, either). From time to time the screen will fade in and out of view. I pulled everything apart looking for obvious damage to the ribbon cable or a connector that was loose, but found nothing. Any suggestions how to troubleshoot which part needs replacement?

Thanks!

 

... and how is the image on an external display? Good? Bad? Nonexistent?

 

Image is just fine on an external monitor.

 

If you're sure all your cables and connections are good, I'd say that the LCD panel itself is most probably broken.

 

Well, no, I'm not sure the cables are good - visibly yes, but that's not worth much here. As far as I can tell there are 3 likely points of failure, the LCD (which works in that it can display an image and the backlight works), the ribbon cable, and the inverter. I'm wondering if anyone has any input from experience as to which of these is the most likely to have failed given the above information.