(adsbygoogle = window.adsbygoogle || []).push({}); Well, I can confirm doing a System Restore does not downgrade your firmware, it just deletes everything. So, CFW (Custom Firmware), is the only way that people who have updated to the 3.21 update will be able to downgrade. So, how do we get a CFW? Geohot has supposably created Custom Firmware, but he is not releasing anytime soon, so I decided to try myself. Well, I have 2 ideas:

Idea 1

This is the easier method. You download the 3.15 custom firmware from here: You must login or register to view this content.
To download you have to register, but I will eventually rehost the files on MediaFire. Then, open up the PUP file using a hex editor such as HXD, and search for the firmware version. I already know it's there. You then try and replace the firmware number to one higher than 3.21 to fool the PS3 into thinking it's an update. I tried 3.22, but that just seemed to corrupt the file, and it won't read on the PS3. My idea is that as this update is non-existant it doesn't work. Therefore, can someone try changing it to 3.2100 like Geohots firmware version? I know this adds bytes, but it's worth a try. You then copy the PUP to a memory stick, and update via removable storage.


Idea 2

This is more time consuming, and I don't have a real clue if it will work. What you do it download Firmware versions 3.10, 3.15 and 3.21. You then compare 3.21 and 3.15, and find any differences. You then compare 3.10 and 3.15, and find the thing that was different in 3.21 that is the same in 3.10 (which hopefully, the only thing that fits this requirment is other OS). We then take the code that enables Other OS, and paste it into 3.21's PUP. We already know you can update 3.21 to 3.21 via removalbe storage, so this could work. Where would you actually put this code in the Firmware? I don't know, that's why this isn't a release.

Neither method should 'brick' or break your PS3, as mistakes will just corrupt the update and it won't read. In order to install the updates, create a folder called PS3 on the removable disk, and make a subfolder called UPDATE. Make sure both PS3 and UPDATE are in Capitals. Then place the PUP file into the UPDATE folder. Also, make sure the PUP is called PS3UPDAT.PUP. Post any questions on the above, or any advancments below. Thanks

Allegedy, the firmwares I linked are dutch :S MasonF123 kindly gave me the US links. They are here: You must login or register to view this content.
Again, they need registeration, but like I said, I will upload the files to MediaFire a.s.a.p.

Interesting.

But I'm under the impression that if a Playstation 3 Update File (.PUP) is modified in any way, it will corrupt the file... that's what I couldn't understand how Geohot achieved it, I mean if it WAS that easy then it would've be done a long time ago... =/

I took a look at the hex between 3.15 and 3.21.

It's completely different.

ill try method one but i cant tell you when i can get around to doing it. If this works it will be good for all the people that have upgraded

↲A long time ago there was no need as you could restore and you didnt loose features

i dont see why sony done this, soon it won't have themes, just the PSN store, the game column on the XMB an system settings lol, sony sucks balls

Not a chance with any of this. Sony isn't retarted. But you can reinstall the same firmware so both are the same version it might work just installing the custom firmware

Well at least we're trying, but I guarantee that gehotz cfw comes from editing a PUP. We just have to find what he edited

I never thought about signing. Still on the off chance Sony messed up big time, it's worth a try, although as I said they were only theories. He did say however that his cfw was just a custom PUP file, but he never mentiond how he installed it. We now may know a reason why, as it's not as easy as updating to a custom cfw. Good thinking! Depending on how the signing works though, modifying the file without altering filesize etc, may keep it valid. I need to test some things out thanks for the help guys