How To Downgrade Ps3 Firmware 4.89 To 4.88

Place it on your USB drive under USB:/PS3/UPDATE/PS3UPDAT.PUP .

Once downgraded, never accept an official Sony update from the XMB. Disable automatic updates in system settings, and always use CFW updates from trusted developers only. how to downgrade ps3 firmware 4.89 to 4.88