That nothing happens when you push the reset button is normal, it only shuts down the unit, but changes nothing in the screen (remember, the screen takes no power as long as it doesn't change).
After pushing the reset button, try to turn it on with the power button. If it doesn't do anything, maybe the battery is flat: charge the battery for a few hours and try again.
If it still doesn't react, you might need to disconnect and re-connect the battery. I don't know if the Opus has a user-replaceable battery. If it does, it should be easy, if it doesn't... well, I hope just charging works
