formatting memstick \ swaping memsticks doesn't matter as all the files are on the flash0 and the memstick is only needed for homebrew\backups etc

as for checking it, hold power slider up for 4 seconds to fully power off, then slide it up to power on and hold Right shoulder button if it boots in to recovery mode you have a 3.03oe-a if it boots in to xmb you have a normal psp.
if you enter recovery mode reply here about reinstalling the 3.03oe-a (you need the data.dxar and oeupflasher or a mate to make you one) or downgradeing to 1.50 (if you not got the data.dxar)

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