Ok so heres the deal,

Many of you know me and know that I recently got YLOD on my PS3. I lost my FFXIII file with 85% trophies and there was no way to get the file off my old PS3 and on to my new one. Until today.

Today I did the blowdryer trick on my PS3 and to my surprise it worked. I managed to get my old PS3 back up and running.The first thing I did was back up all my important files, but then I got to thinking:

Can I use my old FFXIII file, which was made on my old PS3, on my new PS3, and continue unlocking new trophies?

I'm still on the same PSN account the original file was made with.

So pretty much can I just continue my old file and unlock the rest of the trophies on my new PS3.

You shouldn't have a problem if you're on the same psn- I didn't have one when I switched hard drives 

so you just copied your save file to the new HD using a memory stick?

Yep

No you can't.

Save files can only be linked to one PS3. Not one PSN account.

The only way to transfer your save files to another PS3 (so that you can still use the same save files to gather trophies) is by using the Data Transfer Utility.

You know what you should do. just buy a new PS3, and when you get it, take out your old PS3 hard drive and put it in the new PS3. get the platinum trophy on FF13, upload your trophies to PSN. then when your done, change back to the new hard drive and sync your trophies from PSN to your new HDD. problem solved!

You can't do that I'm afraid. The new PS3 will need to format the old HDD...

But the trophy data is verified through PSN once uploaded; I don't see why using a game save generated on a different console would have any effect on that.

Most games that don't want "unlocks" transferred use locked game saves that can't be copied, but admittedly I haven't tested all this out.

I'm currently in the same situation; my primary PS3 died about a week ago and I was only able to copy saves and make an archive after temporarily resurrecting it, but I was unable to get a successful complete console to console data transfer and have since reformatted the drive.

The archive created on one console did transfer some data to the other console, contrary to what I thought would happen, as I was under the impression that archives were completely locked to the console on which they were created.

Not true.

However, locked game saves and PSN content (purchases, DLC, etc.) do not transfer (no surprise there). Non DRM video, photos and music content will also transfer in addition to non-locked game saves. Better than nothing.

While I can't verify FFXIII (I do have a game in progress with archived game saves to test it out), I can say that other games will allow you to "continue" unlocking trophies on a previous game save, even if it wasn't created on the current console you are using.

For what should be obvious reasons, you can't simply swap drives from one console to another and have it start up like normal.

Until someone writes a crack to allow this to work, as soon as you install a drive from a different console that wasn't formatted on the current console, you will be prompted to reformat the drive as the encryption can only be read by the original console on which the drive was formatted.

For the purpose of trophies though, that shouldn't matter as that data is stored on PSN servers once uploaded. Any trophy data that wasn't synched with the servers would naturally be lost if anything happened to the console or drive.

Since you mention an old PS3 and a new PS3, just do what Boutros says.