Acer Aspire 5672 – Blank screen

I have an Acer Aspire 5672WLMi and it is no longer under warranty. When I boot up my computer I get nothing but a blank screen. I can plug it to an external monitor and that works fine. I tried replacing the LCD inverter but that did not work. I tried fnc + F6 to toggle screens but that did not work. I tried swapping RAM and booting it with only one at a time to see if it?s a faulty RAM but that did not work. Anyone else have suggestions? Do you think it?s a fault graphics card? I am pretty sure the graphics card is soldered to the board so it’s not really worth replacing it.