mobile

Hi everyone. I have a strange problem with my Kindle Fire HDX 8.9. It downloaded the software upgrade, but it won't upgrade. Yesterday the device shut down and rebooted in fastboot, than it was completly died. I can't boot it. If I connect with USB cable I get: QHUSB_BULK. The kindle wasn't rooted. The display is black, there isn't Kindle Logo.
Sorry for my bad english