PSP ROMS
A PSP ROM is basically a copy of a game that can be downloaded from the Internet to your computer and then transferred to the memory stick to be played on your PSP. To play these games you must have the correct firmware, it usually means downgrading your PSP. You should be looking for firmware version 1.5, but don't worry I have found a place that not only has literally hundreds of ROMS for you to download but also all the information on downgrading your firmware. It even has step by step guides to help you all the way.
By the way if you want to find out what firmware version your PSP is running just turn on the PSP, go to settings> system settings>system information click X and you will get a message "system software version" 1.0 1.5 1.51 or 1.52.
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