I had the same problem with horizontal lines. I tried unplugging and plunging the cables many times and it did not work. I tried cleaning them and it did not work. Finally I realized that when I change the position of the screen at a certain angle it stops. After an hour of trying to figure it out, I realized that there is a chip like component in the new screen where all three cables are connected to the screen. (See Image) When you bend the cables and try to place the screen in the right position to complete the installation, that chip like component touches the screen itself and it makes flickering. I just places some paper behind that component so that it does not touch the back of the screen. No more flickering. At the end of the day, it was mainly because of the new screen's cable connections. If you can not find the right spot and fix it, return the item and get a new one.

I had the same problem with horizontal lines. I tried unplugging and plunging the cables many times and it did not work. I tried cleaning them and it did not work. Finally I realized that when I change the position of the screen at a certain angle it stops. After an hour of trying to figure it out, I realized that there is a chip like component in the new screen where all three cables are connected to the screen. (See the image) When you bend the cables and try to place the screen in the right position to complete the installation, that chip like component touches the screen itself and it makes flickering. I just places some paper behind that component so that it does not touch the back of the screen. No more flickering. At the end of the day, it was mainly because of the new screen's cable connections. If you can not find the right spot and fix it, return the item and get a new one.