Can my PS3 be downgraded to 3.55?
We can currently downgrade all 16MB NOR PS3 Consoles.
PS3 Slims with Model number 3001A + cannot be downgraded at this time.
How to check your PS3′s Model Number:
Refer to this picture below
The Serial number is indicated by the X’s, and the Model number is on the right.
The model number is CECHA01 indicated in this picture.