Yes you do need it. If you do not have it you will get hardware errors in iTunes.

If you were already having this issue then the fix below will not work. Check the flex cable and clean the contacts with 99% alcohol and a toothbrush (both the logic board and flex contacts). Make sure that the alcohol is at least 92% if you dont have 99%. No need to use much a little will do. Wait a couple of minutes till it dries a put it back together. It should be good. If the screen still is black then your screen needs to be returned.

Is the wifi switch switched on. It should be positioned on the front side of the laptop.

If you are not somewhat familiar wit a laptop tear down I would not recommend you attempting it. If you are up for the challenge then check out the video below: http://www.youtube.com/watch?v=qjP33Faft...

well you cannot set it back to factory settings because you probably do not have the image partition any more. The best thing you can do is download a retail version of the exact OS and input the product key you have. That will make it a valid OS on the PC. If you want the other programs that came on it you will have to go onto Compaqs site and download the from the support and drivers link.

If this is a laptop with a inverter which it probably is you need to check that the inverter was plugged back in. At this point it may seem that the screen is black but it should be showing the picture very faint. if the inverter is plugged in correctly then the issue is the inverter itself and not the screen. It needs to be replaced

Usually once you get that error the board is done unless you get someone that knows how to repair the board "ic repair". What needs to be repaired is under the cap near the battery connector. I have only gotten one phone working after i got that error and it took me trying at least 10 different methods. Here is something I found that worked for others with this issue: Hope this helps... Error code 16 is a hardware issue/fault With my particular phone it was a battery fault I didn't have to buy any new parts or anything I just disconnected and reconnected the battery a number of times. Iv done this 3 times now I have to do it every time I upgrade the firmware and it's worked every time for me. So here's some steps to follow 1. Remove the back with a small cross point screw driver 2. Remove the screw that holds the battery connector 3. pop the battery connector off and and reconnect it 4. Connect device to computer 5. Place the device in DFU mode 6. Once in DFU mode carry out a restore You may have to repeat...

You have to be more specific on the type of device. What year/model is it and want iOS is it running. There are ways to bypass it but different steps for different models.

Go to the Acer website and download the LAN and wireless drivers for your laptop model. That should fix the problem.

99% alcohol and a toothbrush is your friend to fix that issue.