First, brother, this has nothing to do with the charger, whether it is USB or regular charging. Second, you didn’t tell me what system your machine is running on. If you want to play Monster 3, I suggest you upgrade to the system of Prometheus 4. Also, you can either download Monster 3 again or change Monster 3. Copy the files and records to the computer, then use the format in the PSP system settings to format the memory card, and then re-copy the monsters and records on the computer. I think it should work. If you have any questions, please contact me. Help!