PSP HACK HELP PLEASE!?

I have a psp 2001 slim..the version i had before was 5.03..i downloaded CHICKHEN successfully and now i have 5.03 M33..but something is wrong with my psp..whenever i try to load PSPident or a program from my memory stick..it gets stuck on the PlayStation Portable trademark screen and resets..i tried formatting my psp but the version remaiins to be 5.03 M33..i cant get it to downgrade!..i have tried formatting my memory stick as well..