So, you just got your PSP and you find out it's a dreaded TA-082 motherboard. Well, good news! Dark_AleX, Harleyg, Mathiueth, and the team have just made a TA-082 downgrader!
I've seen many questions related to the TA-082 downgrader and how to use it on many forums. So I made this guide because there wasn't one.
It includes all file downloads and instructions. You will need WinZip to extract the files.
Warning: Use of this downgrader could brick your PSP. While it is unlikely when used correctly, all modifications to the PSP's internal flash carry a small risk. Please use with care, PSPHome takes no responsibility for any damage you cause to your PSP.
If your motherboard has "IC1003" on the right, it's a TA-082 motherboard: 
You need a TA-082 motherboard to use this downgrader.
NOTE:
Go to Step 2 if you're already on 2.71 firmware, make sure your PSP is a TA-082.
Go to Step 3 if you already have a 1.50 TA-082 PSP and you want to install cutom firmware.
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1) Update to v2.71:
Click Here to download the v2.71 firmware update.
Open the zip file. Connect your PSP to your computer via USB or card reader.
- Once connected, make the folder called "UPDATE" in the Game folder.
- Put the 2.71 (eboot.pbp) from the (.zip) file into the UPDATE folder on your memory stick.
So now you have:
X:\PSP\Game\UPDATE\eboot.pbp (X is the PSP drive)
Be sure to put in your AC power adapter. Then on your PSP go to:
Game > Memory stick > 2.71 update. Update to v2.71.
Once at 2.71 firmware, reformat your memory stick.
2) Downgrade a TA-082 2.71 to 1.50:
Click Here to download the easy installer for 2.71 TA-082 PSP to 1.50.
Open the (.exe) and state the drive of your PSP. Let the installer copy over the needed files to your PSP. After the files have been copied over on your PSP memory stick disconnect the USB and do the following:
- Make sure you have no UMD's in the PSP drive
- Battery must be charged atleast 75%
- Plug in your PSP in an AC adapter
- Go to Photo --> Hen-D (press "X")
- PSP should do either of the following:
Blue screen + Green screen + Automatic restart = Successful
Blue screen + Red screen = Unsuccessful
PSP crashed/froze = Unsuccessful
If your PSP isn't successful the first time, reboot and try again. You may need to try several times because of the unstability of the exploit. Your PSP will not brick with this, you can try as many times as you want.
- You can check if HEN-D is running by checking under the system information
- After HEN-D is running go into
Game --> Memory Stick and run the IDstorage changer
- After running the IDstorage changer, run the generic downgrader "
X.YZ" and it will downgrade your 2.71 TA-082 to 1.50
- Once at 1.50 firmware, you should reformat your memory stick if you want to continue on installing custom firmware.
Step 3 - Upgrading to Custom Firmware (3.10 OE-A)
Download the easy installer to go from 1.50 to 3.10 OE-A:
Send big files the easy way with sendspace. Files too large for email attachments? No problem!
Make sure you have No UMD's in the drive, and again plug in your AC adapter. Battery must be charged atleast 75%.
Copy
310OEflasher and
310OEflasher% folders to
X:\PSP\GAME
Then, on your PSP, run the updater from:
Game --> Memory stick --> 3.10 OE-A Firmware Install
You may re-format your memory stick after this upgrade.
4) Where to place the files:
Place your ISO's in
X:/ISO (X is the letter of your PSP drive)
Place your homebrew in
X:/PSP/GAME150 (X is the letter of your PSP drive)
You may need to create some of these folders.