hi guys. my friend asked me install a custom firmware (either 3.9 m33 or 4.1 m33) in his slim psp which is currently on 3.9 official firmware. it never had custom firmwares before. although i am familiar with phat psp as i did quite a few before (up to 3.71 m33) i haven't touched a psp eversince. i believe the firmwares are now up to 4.1. someone told me that we can already bypass the pandora's battery route to go to 3.9 m33 and above. is this true for slim psp which never had custom firmwares installed in it before?
would greatly appreciate all the help. i could get hold of the custom firmware files and i only wanted to make sure whether i could install the custom firwmare without the need for a pandora's battery. many thanks.