Tgames and the designers of the programs cannot be held responsible in case of a brick (any installation or update must be done with a full battery or on mains power, do not stop the Psp during installation, etc...) The latest Psps cannot be downgraded below the firmware they shipped with out of the box.
For example if you bought a PSP that was initially on firmware 6.35, you cannot go below that firmware (the real limits are a bit more complex and tied to the motherboard). But! That was without counting on Davee, the developer who designed the downgrader for 6.35 and 6.31. The ChronoSwitch Downgrader v5 lets you take your Psp from firmware 6.60 down to 6.20 for 9g models.
From 6.60 to 6.35 for 7g Psps.
From 6.60 to 6.20 for all other Psps. Usage:
Image unavailable (removed by its host) Download ChronoSwitch Downgrader v5fCopy the "PSP" folder to the root of your memory stick. The downgrader is "signed" and can be launched from an official firmware. You need to copy the official update PSP/GAME/UPDATE/EBOOT.PBP and for the PSPGO it must be placed in internal storage. Run the installation, then just follow the on-screen instructions.
If that's the case, there's a solution, by clicking on this link
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