No display only black screen

There's a difference between "no display" and no backlight.

Try shining a light on the screen while the MacBook Pro is running. Can you see stuff displayed? If so, then the backlight would be the problem, which is controlled by the inverter board. Your replacing it should have fixed that problem. If it didn't, then the display is just bad and should be replaced.

If nothing is displayed on the screen when you shine a light at it, I would recommend replacing the display, or at least looking at its connections to the logic board. They might not be properly attached, or worst-case-scenario, the logic board's display component connectors are damaged in some way, and that would be terrible! It would call for logic board repair or replacement.

It seems like the graphics chip on your MacBook Pro is working well, though, if you're getting video through the DVI port.

Let us know what you find out about the connections. It's probably your best bet to just change the display, though.

That being said, the cheapest option would actually be to replace the LCD alone. Then you'd get a new backlight and LCD, but the replacement is quite a bit more difficult.

Good luck! :)