Ok, a factory version of 2.50 is fine. No, you can use any firmware do upgrade, however there is no need. It is just as easy to downgrade from 2.50.

Follow this tutorial:

1. Download the "Downdater" from http://dl.qj.net/index.php?pg=12&fid=8566 The password for the archive is " I_Use_It_At_My_Own_Risk" without the quotes.

2. You need a dump of the 1.50 flash, which HAS to bee dumped from a 1.50, by DOWNDATER HELPER, which is included in the archive. If you know someone with a 1.50, please use that, because distributing the files is illegal. Otherwise, PM someone who has downgraded, and they may be able to help you out.

3. Place the folder which you "legally aquired" called "DOWNDATER" into the root of your memory stick.

4. Place the folder "DOWNDATER FINAL AUTO EBOOT" into the PSP>GAME folder on your memory stick.

5. Ensure the GTA eloader is installed and working.

6. Plug in the AC power adaptor

6. Boot up GTA and the Eloader, and select "Downdater test"

7. The Memory stick light will immediately start flashing, and will do so for a while.

8. The PSP should reboot itself into the screen you saw the first time you switch on a PSP; Set the basic preferances.

9. Your PSP should now be a v1.50.

You may encounter UMD errors that say "The disk could not be read". This is because the Drive hasnt reset properly, so remove the battery pack for 5-10 minutes, and they will stop. We suggest upgrading to 2.00 and downgrading back to 1.50, because the actual downgrade method we used is messy. This way, you will have a clean installation.

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