How to get and install custom firmware?

[davebgb]

Being new to this I am having some difficulty.

I have downgraded my PSP to V1.5 but would like now to install a trusted custom firmware version.

Now that Dark Alex has gone and his site is off, where can I download firmware V3.40 oe from and how do I install it?

Some help would be much appreciated.

Thanks in advance.


Thanks for the help guys. I have now downloaded 3.40oe but the readme is confusing what is meant by the sony updaters and where should I get these from? What program do I execute? is this readme instruction complete? do I not have to flash something into the PSP. Sorry for being so dumb:-
Installation instructions:

- Copy oeupdmaker and oeupdmaker% to /PSP/GAME if you are in 1.50, or to /PSP/GAME150 if you
  are in any SE/OE version. Get the 1.50 and 3.40 Sony updaters (of any region, because all are
  currently the same), and copy them in the oeupdmaker directory with the names 150.PBP and 340.PBP.

  Execute the program, and it will generate the DATA.DXAR file. The checksums (althoug the flasher
  will check for them for you):

  CRC32: CDA4638D
  MD5:   9754F2CC0CBE2D8FE0DD009C90FDCD9F
  SHA1:  6F76BB67B31EFF6FECB72D9D4AF443C793E1E521

- Copy 340oeflasher and 340oeflasher% to /PSP/GAME if you are in 1.50, or to /PSP/GAME150 if you
  are in any SE/OE version. Move the DATA.DXAR to 340oeflasher directory.
  
  You need 75% battery, although you can skip this if you pressed L+triangle while loading the program.

[Fanjita]

dl.qj.net is usually a good source of archived downloads.

[wakaru]

As for the instructions, they usually come in the way of a README.TXT file within the compressed package. So check the file and follow the instructions. It shouldn't be too difficult.

[Benranger959]

Try the psp upgrader/downgrader program that can be found on the official psp fourms. You enter your firmware(1.5) and the firmware you want to go to(3.40 OE-A) and then it does it for you and all you have to do is run it off the mem stick.