MacBook unibody A1278 wont boot with brand new lvds cable connected.

Hi,

I recently purchased a used macbook unibody A1278 with a damaged screen. The computer booted and ran properly but the screen wasn't backlit and had faint lines running across it. I connected it to my tv with a mini display-port and everything works properly.

I purchased a brand new screen but it didn't work at all and i realized it was probably an issue with the LVDS cable.

So I bought a new lvds cable, hooked everything up and now the computer boots up only until the chime and then it cuts off. But if I unplug the lvds at the motherboard, it goes back to booting up properly.

I feel like I've gone through all of the related topics and have seen the different steps to diagnosing the problem but none have helped me thus far.

Can anyone help me out?