Fixed it myself.
My 580P was out of warranty and I'm impatient. It's basically the antenna lead wire that gets detached due to a poor solder joint (very little solder).
The symptoms is:
Unit is powered on, stays on the "Locating Satellites" screen with the progress bar cycling from 0% to approximately 5% (hard to tell since no number progress is shown).
I never dropped my unit, but while I was out riding today, I crossed a set of railway tracks and lost the GPS signal. Hard reset (hold power button for 10 sec), factory reset, gps reset when prompted all do not help. Firmware version 1.03 or 1.04 update will not help. The only thing that will fix this is to send it back for repair... unless you want to risk opening it yourself which I don't recommend unless you know what you are doing.