Is my backlight inverter out on my HP laptop?

I have an HP dv2840se and after a couple of years I saw red lines (weird) across that appeared horizontally across the screen. They were seldom off and on, until the third and final year (recently) when the screen starting going completely out like a bad sketchy video tape and has gotten worse to the point where I can't use it. All I see is a lit screen but no windows logo at startup or anything. So I guess this means the lamp (or whatever it's called) doesn't need replacing? Just the inverter? The screen is bright but black and can only adjust the brightness with the keyboard. I'm using my iphone now, it's sad. I found an inverter for $30, i will try to install it myself. My computer got A LOT of usage since I'm a student.