| You have to format your memory card if your card is not the one that came with your psp. If you are thinking about formating the one that came with your psp you don't have to. If you don't format the none psp card that comes with it you can't use it. When formatting your card it ERASES ALL DATA which means you'll have to back it up. I don't know why but it decreses your maximum amout of megabytes left. (This is normal). So... after formating a 512mb card this is what happens:
#1 All data is erased (back it up first)
#2 Decreses the maximum number of megabytes
#3 If memory card is not the psp one it enbles you to use it | 
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