How to Downgrade My Firmware of PSP Slim
- 1). Slide the power button upward to turn the PSP off. Remove your normal battery and normal Memory Stick. Place these aside.
- 2). Insert your Magic Memory Stick into the PSP card slot, followed by the Pandora battery into the PSP battery cradle. You need to insert these in this order or you will be unsuccessful. When you insert your Pandora battery all the way, your PSP will turn on automatically.
- 3). Wait as the black screen is populated with white text. Read through this text. You will have the option of installing custom firmware, which is firmware created by independent developers, and you will have the option of downgrading your PSP firmware to 1.50.
- 4). Press the "X" button to downgrade your firmware to 1.50. Wait as the PSP is downgraded. Once the process is complete, you can install the custom firmware or just run the PSP 1.50.
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