How To] Downgrade Firmware on PSP Fat/Slim From 6.60 to 6.XX In Less Than 7 Minutes - YouTube
I need an expert's advice. I bought this PSP and I want to hack it. The problem is I'm not sure if I can downgrade this firmware since its a permanent csw?
Picked up a PSP-1000 on firmware 1.0. Any reason to NOT be on 6.61? : r/PSP
How to downgrade your PSP Firmware with Chronoswitch - Darthsternie's Firmware Archive
Chronoswitch Downgrader | PSP.SceneBeta.com
How can I safely downgrade my Sony PSP firmware? - Ask Dave Taylor