My iPhone 3G screen and touch screen does not work!

[danya101]

How it all started was that the power button on the very top of my iPhone 3G stopped working and i wanted to take it apart and see if I could do anything about it. I followed the correct instructions to take it apart and made sure that I was grounded the entire time. I couldn't figure out how to fix it so I put the logic board and everything back exactly as it was but when I plug it into my computer (which is the only way I can turn it on as the power button is broken) the screen did not turn on as usual but after about a minute (the phone was turning on) my computer recognized it and it started syncing with itunes, all while the screen remained blank. I heard sounds of emails I was receiving and I even tried unlocking it and entering the passcode but it seemed that the touch screen was unresponsive as well. I took it apart again and inspected the three connectors (one for the LCD screen, one for the touch screen, and a smaller one for the speaker) and found no bent pins or loose connections. I reconnected all three and closed it up. There was still no response from the LCD or the touch screen but I could still sync and receive calls and emails. I then tried resetting it and installing the latest firmware, yet the screen remains blank and the touch screen unresponsive. Does anyone know what could possibly be wrong and how can I fix this?