The other day, after about 2 years of flawless service my 530 started rebooting upon turning it on. I looked down at it while I was preparing for a ride and after the Garmin logo was on the screen there were three consecutive dots flashing in sequence, about 4 seconds the unit would reboot. Sometimes this happened 3 or 4 times before it would actually boot into its normal running mode. After searching online I decided to just do a complete factory reinstall and it still hangs on that screen again, although for only 1 reboot before being operable.
I would think a factory reinstall would cure almost anything.