my ipad is broken ;/

Hi.

In the begining everything was fine with my ipad. After that i had some problems with port in the bottom. When i am pluginig ipad into computer (windows 7) i have message "a device wasn't recognised" and i can't connect to the computer. I tried with diffrent cables and computers every time same message. Also i cant charge ipad. When I am pluging ipad into electric socket nothing is happening.
The problem is i have JB on ipda so i cant put it into warranty. (i cant connect to restore to original soft). However I decided to put it into service. Before that in settings -> reset-> i chose erase data to clean my ipad. After that ipad is bricked. I can put it into recovery mode but still i can't connet to computer to restotre it. The question is, am i lossing my warranty when i put it into authorized servis?
After that proces (erase data) when I turned it on i have only black background and apple logo in the middle. Will apple service recognize then i JB ipad?

Sorry for my english.