All the device does is shows up as this in the windows device manager. It will not react to any button/button combinations. Is this basically bricked?
Even disconnected from comp? Was it rooted, recovery or had a custom ROM? Did your phone work before??
I had a similar problem with my phone being not recognized on my comp, but my phone worked fine when not connected. It was a driver issue. Uninstall current driver and reinstall a fresh driver package and give it a shot. But if your phone isnt working at ALL, thats a diff story
Yup just a black screen regardless what I do. I was rooted, messed up and said to update the OTA and then fell into this mess. I am guessing its shot at this point but though I would ask the question.