Continuing Video Problem on i8100

I've been having a video problem on my i8100 for about 6 months now, and I'm getting ready to throw this thing out the window.  The backlight stopped working one day, after never having a problem before.  I tried replaceing the inverter and ribbon cable with no success.  Last month I finally bought a LCD off of ebay and that still didn't fix the problem.  Next I bought a Geforce 2 32mb and still have a black screen.  My next and last step is to replace the motherboard, and I can only hope that will fix my problem.  Does anyone have any other ideas before I spend another $200 on something that may not work?  It originally had a Toshiba LCD and I've got a Samsung or Hitatchi display now, I forget which one.  I've read a lot of posts about one of those 2 brands not working a lot, and I know this is not that brand.