Compaq c700 laptop LCD gone dark and new inverter AND new LCD doesn't fix it????

[redgtxdi]

So I'm fixing a laptop for someone at work. It's a compaq c700 whose screen went dark. You can see the desktop, just no backlight. So I figured inverter first, then LCD. Inverter was $5 but didn't fix it so I told her instead of trying to replace just the lamp, let's just replace the whole LcD. Replaced LcD tonight and it's still dark.

Any ideas?

P.S. yes, both video cable and two wire white/pink cable only go in one way so it's a go or no situation and in this case it's a no go. I fixed my mothers laptop before with this same prob doing the same process so if it's not inverter and not LCD, what else is there for backlight?

TIA

 

[redgtxdi]

Bump! Can a problem at the motherboard create a situation where the video still comes thru but keeps power from getting thru to light the bulb?

TIA....again.