Dell XPS M1530 problems

[Busta_Gonad]

I'm after some help from one of you wonderful geeky ones

I have a DELL XPS M1530 in on trade, the screen is totally black when turned on (its one of the famous need reballing graphics chip ones

My issue with it is, I dont think this one has a faulty chip, It works perfectly on external, and if I do the fn+power diagnostic the screen flashes the colours as its supposed to. My question is where do I go from here?

I've tried a different screen in it, I've tried a different Invertor in it, and I've tried a different cable in it (I've also tried various combinations of all three

Any help out there?

 

[The Dentist]

i had two machines this happened on. an asus rock and a dell xps m...something. both had the nvidia graphics chip.
on the asus i put some new thermal paste on which helped for a month but to be honest, its a dying machine. when it happened second time i couldnt get it back to life.

 

[Busta_Gonad]

my only doubt of this, is that it works fine on an external monitor

 

[The Dentist]

my only doubt of this, is that it works fine on an external monitor

ah ok. does it work for prolonged amount of time? then it be the screen or one of the connectors to the screen (stating the obvious) lol. do you have one of them electrical testers? i take it you have changed the screen?

 

[Busta_Gonad]

yeah it works fine continuous on an external, i've changed the screen, i've changed the invertor, i've changed the cabling, still nothing on screen.

When i run diagnostics, i get PSA+ 2000-0321 code which is Unable to detect LCD.