WORKS WITH TA-082!!!!!!!!!!!!!!!!!!!!!!!!!!!!
This thread will help you downgrade any 3.03 PSP to 1.50, in only 8 steps.
Downgrading requires an unpatched copy of Liberty City Stories. The LCS that upgardes your PSP to a 2.00. This downgrade will only work on PSPs with 3.03 firmwares.
If you have any questions about the downgrading process, I suggest posting them in this thread. I will respond to PMs asking for help, but due to the overwhelming amount of PMs I've recieved in the past 24 hours, it is going to take me a long time to respond to everyone. Questions posted in this thread get first priority over ones I've received via PM. Thank you for your cooperation, and good luck downgrading!
How to downgrade firmware 3.03 to 1.50 (works with all PSPs)- Download and decompress Downgrader for v3.03 PSP
- Copy the PSP folder from the "MS_ROOT" folder you just downloaded to your PSP. If you already have a "PSP" folder on your PSP, re-name it or back it up first, so it isn't overridden by this new one

- Download and unzip the 1.50 Upgrade Eboot, name it "UPDATE.PBP", and put it in the PSP/GAME/UPDATE folder on your PSP

- On your PSP, run an unpatched copy of GTA: Liberty City Stories. It will load a savegame, then the screen will go from black to blue, then the PSP will restart itself. This enables HEN, which is required to downgrade.
- On your PSP, go to the "GAME" menu. Choose the "MEMORY STICK" submenu. Run the PSP Update ver X.YZ program

- If you have a TA-082 or higher motherboard, you will be prompted to allow the downgrader to patch your motherboard so it can be safely downgraded. The downgrader will not let you proceed without patching.
- The program will display an agreement. Press X to accept. Don't shutdown the PSP and don't remove the memory stick until the update is finished.
- Once finished, shutdown the psp and restart manually to 1.50
- Erase the PSP folder