Sony has confirmed that you will not need to log into your PSN account on the PS3 that you created that account on only.
Earlier today, Sony held a press conference regarding the recent PlayStation Network hack, and provided several details on what steps will be taken from here on. One of the points that was mentioned by the translator was that the user’s PlayStation Network account password will need to be changed as soon as he or she logs into it once the network is back online. During this point, it was also mentioned that the password could only be changed “on the same PS3 the account was created or activated.” This can be heard around the 13:30 mark on the press conference video. The press release that was also uploaded during conference states:
Click on image to enlarge:
As an added layer of security, that password can only be changed on the same PS3 in which that account was activated, or through validated email confirmation, a critical step to help further protect customer data.
This has led many to believe that their accounts are lost, as a lot of users have been forced to buy a new PlayStation 3 due to hardware failures in the past. Sony Computer Entertainment Europe’s community moderators have confirmed that you do not need to log on to the PlayStation Network with the PS3 that you created your account on.
As long as your account is also activated on your current machine (i.e you have downloaded content to it previously) you should be okay.
So, as long as you didn’t deactivate your PlayStation Network account through account management, you will be able to log in and change your password.