To be eligible to downgrade, it is necessary that the PS3 has a native firmware equal or less than 3.55.
All PS3 FAT are eligible to downgrade, however, the PS3 Slim are not all compatible, mistrust !
To prevent the brick risk of these onsoles, tito1 offers a small PS3 utility that allows you to know the minimum version of firmware that could accept your console in case of downgrade.
Process:
1. Take a blank USB key and place the contents of the "ps3_minimal_firmware_checker" folder to the root
2. Insert the USB Key into an USB port of the console switched on
3. From XMB, go into Settings -> System Update -> Update via Storage Media -> VERSION CHECK by Ifcaro and press "X"
4. The update will fail with a message stating you the initial firmware version of the console : "Update data of version X.XX or later can be installed on this sytem. (8002F967)"
PS3 Minimal Firmware Checker
