Going From 3.80 To 3.80M33 On Your PSP
I have seen queries asking that now Dark_Alex released 3.80 M33, if people can install custom firmware on their PlayStation Portables running the official Sony 3.80 firmware. This seems to be a common misconception, the problem is not the “version mismatch” that people thing, because you can replace any firmware version on your PSP with a custom firmware. Instead the problem is the inability to run the homebrew custom firmware installer that will do the actual replacing. Hackers have found many solutions over the years, including exploits in games like GTA and Lumines that downgraded your PSP to Sony firmware 1.50 where it was much easier to run installers. But those only work for specific firmware versions; for example, there is not gaming exploit past firmware version 3.50, which means that the only way to install custom firmware on a Slim PSP is to use what is called a Pandora’s Battery.
I am no expert on this topic, because all PSP’s that I had were Fat and so easily downgradable. With Slim it is a bit more complicated, because there is no firmware 1.50 for them. Instead you run the actual installer that installs 3.80M33 directly, which I believe is called Del Camentino Universal Unbricker. There are a lot of online guides that will guide you through the process. I have compiled a list of them before when I talked about downgrading firmware 3.73, and they still apply to firmware 3.80. So check out the list below.
SoftModding Tutorials (Needs An Already Modded PSP)