iPad 4 GSM errors while update/recovery

Hi,

my iPad 4 GSM errors, with error (1) when trying to recover.
When plugging in the cable iTunes recognizes that an update (8.3) is available and tries to download and deploy it - but after a while the operation fails after about 55-60% and the system freezes.

I have no backup yet - so there seems to be no other suitable option than recovering.

Edit: Tried it on a Mac and PC with iTunes and 3 different cables.

What else can I do to get the system in a usable condition again?

best regards

Message was edited by: hanktd