I saw considerable traffic from my 3.80 M33 is released post look for a way to convert from Sony’s official Firmware to the current one so I thought of making a guide for it.
Okay I lied part of the title. I was supposed to start off with a How to on downgrading but so you don’t mess anything up, why don’t you just use the guide I followed. It’ll help you downgrade your PSP (Phat for Slims you need to use this guide) to 1.50 and allow you to install custom firmwares.
Note 1: Make sure your PSP is charged to at least 78% or is connected via AC adaptor before you decide to change firmwares
Note 2: DO NOT, I repeat, DO NOT reset, turn off, or interrupt your PSP while upgrading/installing firmwares otherwise you’ll end up bricking it.
Note 3: If you have questions post them below. I’ll try my best to help you.
Note 4: The guide was made from a collection of Readme’s from all the mentioned CFW dumbed down so even the most novice of PSP users will understand. If you still miss something, post a question.
On with the Guide:
Installing 3.52 M33 on a downgraded PSP (1.50)
Requirements:
- A PSP on 1.50 Firmware. Downgrade or A PSP with any OE firmware
- PSP battery that’s at least 78% full
- The 3.52 M33 installation file
- A USB cable, to connect your PSP to a PC.
Installation of 3.52 M33 on 1.50 Firmware:
- Extract the 3.52 M33 files to your computer.
- Copy the folders ‘kxploitpatcher and kxploitpatcher%’ to the directory; ‘X:/PSP/GAME/’ on your PSP’s memory stick.
- Copy the folder ‘M33CREATOR’ to the directory; X:/PSP/GAME/ on your PSP’s memory stick.
- Download the official 3.52 update and rename to 352.PBP.
- Copy the 352.PBP to the directory; X:/PSP/GAME/M33CREATOR/ on your PSP’s memory stick.
- Download the official 1.50 update and rename to 150.PBP.
- Copy the 150.PBP to the directory; X:/PSP/GAME150/M33CREATOR/ on your PSP’s memory stick.
- Run ‘3.52 M33 CREATOR’ under GAME on your PSP
- Run ‘3.52 M33UPDATE’ under GAME on your PSP
- After all process is complete, press X. Your PSP will reboot.
- Congratulations, you’ve just installed 3.52 M33
Installation of 3.52 M33 on OE/M33 Firmware:
- Extract the 3.52 M33 files to your computer.
- Copy the folder ‘M33CREATOR’ to the directory; X:/PSP/GAME150/ on your PSP’s memory stick.
- Download the official 3.52 update and rename to 352.PBP.
- Copy the 352.PBP to the directory; X:/PSP/GAME/M33CREATOR/ on your PSP’s memory stick.
- Download the official 1.50 update and rename to 150.PBP.
- Copy the 150.PBP to the directory; X:/PSP/GAME150/M33CREATOR/ on your PSP’s memory stick.
- Run 3.52 M33 CREATOR under GAME on your PSP
- Run 3.52 M33UPDATE under GAME on your PSP
- After all process is complete, press X. Your PSP will reboot.
- Congratulations, you’ve just installed 3.52 M33
Now in order to switch from 3.52 M33 to 3.71 M33, you need update 4 of 3.52
Installation of 3.52 M33-4 Update on 3.52 M33:
- Download 3.52 M33-4 and extract it to your computer.
- Copy the Update folder to X:/PSP/GAME/ on your PSP’s memory stick.
- Run 3.52 M33-4 UPDATE under GAME on your PSP
- After all process is complete, press X. Your PSP will reboot.
- Congratulations, you’ve just installed 3.52 M33-4
As a precaution, format your Memory Stick or delete all used files before proceeding. After which you can proceed to the next installation.
Tagged with: Custom Firmware, Playstation Portable, Tips
Filed Under: Playstation Portable


















well when i apply the 3.52m33-3or4 update my psp stick to the save data option in the game menu after the reboot is done. what shall i do?
Wow this is the manual way of doing the upgrade. I used an easy installer for mine .
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yep. Doing things the hard way is the best for some people (easier to get at the top of SERPs too ^^)
Note.. to jay (guy with the reply) I still don’t understand what you’re trying to say =(
i have a ofw psp and i want to convert to a cfw ..what should i do please help me please…i dont have a pandora battery
[re=1504]Aerial[/re]: Read my most recent post for an easy to follow guide to making a pandora battery
Amazing article! Detailed and very interested. I am going to recommend this blog to my friends.
I have ofw 3.80 i want to install cfw 3.71 m33 how can i go forward.
Can i play games without umd if i upgrade it to 3.71 m33 CFW.
from where can i get free games and how to play it and put it in which folder.
Please help me out i will be very thankfull to you.
Has anyone tried to downgrade FW5.2 to 1.5? Really appreciate anyone that could walk me through from doing it. I want to install the CFM 5.00 M33-3. thanks
Hi, I’ve got a PSP 1000. It’s firmware is 2.50. How do I upgrade it to a 5.00 M33?
Also, I just myself a Hybrid pandra battery. So do i just need to download the firmware 5.00 M33. Could you plz guide me. It’s my first time with all this.
Many thanks
I’m going to redo this post sometime soon to include a proper installation guide. Please bookmark and come back again.
so if i have phat psp that is version 5.51 can i still turn it to 3.80 M33 CFW?!
dooo i neeed pandora battery
well…I have phat psp with v 5.03 I tried evrything I could to downgrade it to 3.90 or less but nothing I never tried pandora’s battery but I tried pandora’s battery without cutting it still refuse to downgrade even any kind of program won’t work at all please hellp me
Why would you want to downgrade to 3.90? Well in any case, follow this guide:
http://www.atmaxplorer.com/2009/07/convert-your-psp-to-custom-firmware-without-pandora-battery/
I’m relly sorry…but still nothing
Chickhen + Hellcat’s didn’t downgrade your PSP?
# Extract the 3.52 M33 files to your computer.
# Copy the folder ‘M33CREATOR’ to the directory; X:/PSP/GAME150/ on your PSP’s memory stick.
# Download the official 3.52 update and rename to 352.PBP.
# Copy the 352.PBP to the directory; X:/PSP/GAME/M33CREATOR/ on your PSP’s memory stick.
# Download the official 1.50 update and rename to 150.PBP.
# Copy the 150.PBP to the directory; X:/PSP/GAME150/M33CREATOR/ on your PSP’s memory stick.
so we need 1 M33CREATOR in GAME150 folder and 1 more M33CREATOR in GAME folder???