All of the above have worked for me but on one occasion I had the same problem with 2 ipod 4th generation devices. After replacing the screens I had nothing (black screen). I tried unplugging and reseating the cables and then the screens would power up with a white screen or still do nothing. Did this several times with no luck. I tried shorting the battery (3.7v pin to ground) and this had no effect. I finally plugged them into a computer to see if itunes recognized them and it did. What I discovered was the software was a verstion 5.x.x and iTunes was telling me I needed to update the software. I updated the software on both devices to 6.1.x and then plugged the screens back in. Both powered up with a white screen and I did a reset (home button and power button for 10 seconds) and both devices powered up with no problem. I read somewhere on the internet that the new screens coming over from China have an lcd on them that is not compatible with older software versions. Cory

I had the same problem with 2 ipod 4th generation devices. After replacing the screens I had nothing (black screen). I tried unplugging and reseating the cables and then the screens would power up with a white screen or still do nothing. Did this several times with no luck. I tried shorting the battery (3.7v pin to ground) and this had no effect. I finally plugged them into a computer to see if itunes recognized them and it did. What I discovered was the software was a verstion 5.x.x and iTunes was telling me I needed to update the software. I updated the software on both devices to 6.1.x and then plugged the screens back in. Both powered up with a white screen and I did a reset (home button and power button for 10 seconds) and both devices powered up with no problem. Cory