Downgrading to very old OFW from new CFW

Jollyroger

Forum Noob
Everyone, I would like to ask for your support to understand what is the best procedure to downgrade a CFW 4.89 machine to OFW 3.15 (last official one to support OtherOS).

While I understand that soon we may have the fantastic CFW 4.89.3 which should bring back OtherOS functionality, I don't have complete knowledge of the features and limitations to install one of the older Linux distributions, such as Fedora 6/7 or Yellow Dog, so at least for now I would like to install 3.15.

What is the recommended procedure to downgrade to a OFW that old (older than 3.55)?

Also, what is the reverse procedure, from OFW 3.15 back to CFW 4.89?

Thank you in advance!
 
enable qa flag first (if it is not already enabled). leave it enabled even after you are done downgrading.

after that, you can downgrade just by installing the older firmware.

when you are done on 3.15, AFAIK you can just install any recent cfw on top of it. (if 3.15 will not allow cfw pup install directly, i know that 3.55 will allow it.)
 
enable qa flag first (if it is not already enabled). leave it enabled even after you are done downgrading.

after that, you can downgrade just by installing the older firmware.

when you are done on 3.15, AFAIK you can just install any recent cfw on top of it. (if 3.15 will not allow cfw pup install directly, i know that 3.55 will allow it.)

Thank you Coro. I recall reading somewhere that downgrading directly to 3.15 directly from a recent CFW may not work (something to do with package management?), is it something anyone can confirm?
 
Will work... That's why You need QA flag. Otherwise downgrading will be impossible without messing with update package version (de facto making CFW 3.15).
 
Thank you Coro. I recall reading somewhere that downgrading directly to 3.15 directly from a recent CFW may not work (something to do with package management?), is it something anyone can confirm?
Will work if you set the QA flag, but this will only work if the console had 3.15 or lower when you first bought it. The general rule is that consoles cannot be downgraded to a firmware version lower than the one they originally came with.
If you're not sure what's the minimum supported version here's a list of all models and the minimum version they support:
SKU Models - PS3 Developer wiki (psdevwiki.com)

IF YOUR CONSOLE DOES NOT SUPPORT 3.15 DO NOT TRY TO INSTALL IT. At best it'll refuse to install it, worse case you'll end up with a brick.

EDIT: Seems that all phat models support 3.15, but only the earliest Slims (20xx) support it. Other Slims (21xx+) don't. Obviously Super-Slim don't support it.
 
Thank you everyone!
My PS3 is a phat CECHK01, which I purchased specifically to install Linux, so that should be fine, yes?
 
yes. it should be able to install 3.15...UNLESS maybe it was refurbished by the factory.
 
Is it not possible to check on firmware 4.89 or other recent version firmwares? At least it used to be possible to check the lowest firmware that can be installed. There was a minimum version check and also, IIRC an app to check the version.

I believe you can check by using update manager to ask the syscon, maybe at offset 2F00? You could probably find out for sure by consulting that wiki mentioned above.

It is generally true that the minumum version, is the version it came with, but that is not absolutely always 100% the case. I have a ps3 that came with 3.50, but is downgradable to 3.40. IIRC, I downgraded it to 3.40 before installing 3.41. Though not sure about installing 3.40, definitely 3.41. Someone mentioned, they some times pull one off of the line to test with newer firmware. This was long time ago, and no further explanation was given.
 
So, I activated the QA flag using the CFW menu and put the OFW 3.15 PS3UPDAT.PUP in the proper place on a USB key, but when I go to do System Update (from USB), it tells me that there is no update available.
I also tried to boot the PS3 holding down the power button to activate the restore mode, but after holding the button for a while, instead of beeping twice and getting restore mode, it turns itself off...
Thoughts?
 
it tells me that there is no update available
HERE is my pup install guide. try the troubleshooting tab.

after holding the button for a while, instead of beeping twice and getting restore mode, it turns itself off...
To enter Safe Mode:
  1. Begin with the PS3 turned off. The power light should be red.
  2. Press and hold the power button untill the PS3 beeps three times and shuts down again. The power light should be red again.
  3. Press and hold the power button again. You will hear a beep, then another beep, then a double beep. Let go of the power button after the double beep.
 
BTW if your ps3 does not beep anymore, the light on/near the button will also flash when it tries to beep.
 
HERE is my pup install guide. try the troubleshooting tab.


To enter Safe Mode:
  1. Begin with the PS3 turned off. The power light should be red.
  2. Press and hold the power button untill the PS3 beeps three times and shuts down again. The power light should be red again.
  3. Press and hold the power button again. You will hear a beep, then another beep, then a double beep. Let go of the power button after the double beep.

Thank you Coro, I did what you recommended and managed to get to the recovery menu.
When I selected the system update it asked me to insert a USB key with a firmware version 4.89 or higher.

I pressed select anyway, and after a while the process stopped saying "The data is corrupted. (8002F2C5)"

After turning off and back on, I checked the status of the QA flags and all COBRA menu items report "Syscall 8 disabled or partially disabled"... ideas?
 
Last edited:
Just to check that your USB drive works fine and that you have indeed activated the QA Tokens, go to Settings -> Network in XMB and press the button combination

:dir down: + :but l1: + :but l2: + :but l3: + :but r1: + :but r2: (all pressed at the same time).

If the QA Tokens are valid, you should see the Debug settings.

One useful option in this menu is System Update Debug. Once you turn it on, you can place up to 20 update PUPs in your HDD and load them from the System Update option in XMB and update your console via the PUPs stored in your HDD (that way we can rule out an USB drive failure).

upload_2022-10-13_8-55-14.png


To do this, just create a folder in /dev_hdd0 named updater, and inside of it create another folder numbered 01 and place your PUPs in there. I.e. you have Evilnat 4.88, Evilnat 4.89, CFW 3.55 and OFW 3.15, so you should create folder 01 inside updater and place the PUPs inside (which can have any name you want, without the PUP extension too!).

Code:
dev_hdd0
|- 01
   |- EVILNAT 4.88
   |- EVILNAT 4.89
   |- CFW 3.55.PUP
   |- OFW 3.15

Source: https://www.psx-place.com/threads/how-to-use-debug-update-tutorial-by-pinky.158/
 
Last edited:
Thank you for the tips.

When pressing the key combination I can see the the Debug Settings menu.

I used multiMan to copy OFW 3.15 PUP to the dev_hdd0/01 folder as you recommended, but when selecting it in the "Update from System Storage" menu, it still fails to update.

Here is what I did to make it work:
1) I made sure the QA flags were active
2) I downgraded to Rebug 3.55.4, as it seems the key used on OFWs < 3.55 was removed from subsequent versions and so it is not possible to directly install OFW < 3.55 from CFW > 3.55
3) Once Rebug 3.55.4 was installed, it still failed to update to 3.15 from XMB, so I used Recovery Mode and installed 3.15 from there

This did the trick, the PS3 is now OFW 3.15 :-)
 
Looking at this thread, is it possible for me to downgrade a Slim console running CFW 4.87 to OFW 4.55 where the earliest it was shipped with was OFW 3.40?
 
Looking at this thread, is it possible for me to downgrade a Slim console running CFW 4.87 to OFW 4.55 where the earliest it was shipped with was OFW 3.40?
Yes. You should first downgrade to a CFW <= 4.55 then install OFW.
 
Yes. You should first downgrade to a CFW <= 4.55 then install OFW.
Excellent thanks! So i have to go from my CFW 4.87, down to CFW 4.55, and then move over to OFW 4.55 then?
I can't go straight from CFW 4.87, down to OFW 4.55? (why?)

Where can I get a CFW 4.55?


I'm on EVILNAT 4.87.2 right now, if that makes any difference to the answer.
 
You cannot go down below factory fw version (PS3 will reject it before install). You didn't tell us Your PS3 model so probably Yours started from 3.50.

If You are able to install such old fw, You need make one checkpoint at 3.55. And the same when You will be upgrading. You can install 3.55 from any 4.xx if have set QA flag (without it, no downgrade is possible at all anyway). You cannot install Evinat CFW from 3.55 for unknown reasons (but Rebug Rex/Lite are fine and from them Evilnat if You want).
 

Similar threads

Back
Top