Laptop Display Problems

I have a Dell Vostro 1500 laptop. Recently, the screen started randomly flickering. Then about a week ago, it would flicker during startup, and the screen would become dim. It wasn't completely black, but I could barely see the screen. I have heard that this is either a backlight or inverter problem- is this true? How would I know which one is causing the problem? I connected the laptop to an external monitor, and it worked fine. Now it has been working normally without being connected to the monitor for the past few days. What should I do?

 

That would be a inverter problem. I would contact Dell and see what their charge is for a new inverter. You can buy one for around $40 and change it out yourself if you are comfortable in doing so.

 

I just searched on Amazon and found one for about $12. It doesn't seem like it will be too difficult to install. Thank you for your help!