i have a NAND PS3 and I installed the 3.55 OtherOS++ . petitboot froze on its first time running. i tried to use my keyboard, but it was completely frozen. so i had to do a hard power off. after this it black screens at trying to get to recovery menu, gameos and service mode.
I have tried formatting my hard drive and that didnt work either.
Any help would be appreciated.