The PSP firmware downgraderという記事。

About a week ago, I mentioned the PSP firmware faker which tricks your PSP into thinking it’s running version 1.50, but now there is a real, working downgrader available!



SXT Firmware Loader Beta 1 for 1.50 PSP's

SXT has created a firmware loader for 1.50 PSP’s that will load all firmwares 2.0 and below.

これで心置きなくファームウェアをアップデートできる? at your own riskでお楽しみください。