|you replacedt he inveter but you havent replaced the screen it self? a screen and inverter from ebay can cost anywhere from £30 to £80 depending on make and model.|
personaly i would take the entire screen off the check behind to see if the ribbon has come loose, also take up the keyboard and see if any cables/wires have come loose there.
i always replace the inverter and screen together, rather than just one, thats just the way i roll, it just eliminates all other possible problems. i could recommend the seller i buy from on ebay if you like, their inverters come attached to the screen so its a simple as screwing the new screen to the laptop.