Hello everyone this is my first post and first time trying to mod my friends psp or any other psp. my friend has Fw 4.05 is there any way to downgrade from there or is he stuck, my other question is i tried to hardmod the battery but it looks different from the guide, this battery has the little chip on top of the battery can i still do this and how? this is a genuine sony battery its the PSP-110 1800mAh 3.6v. if i cant should i use the Datel Service Tool as the last resort

Well Thanks for your time