PSP玩家们又将为之疯狂了， Noobz 给我们带来了新年最大礼物PSP 2.81－3.03官方系统降级程序，本降级程序支持(TA-079到TA-086)的全系列主板，也就是说目前市面上所有的主机都可以降级到1.5版本，都能直接玩ISO游戏了。

电玩巴士实机测试成功

引用：
------------------------------

Here is a guide for downgrading any current PSP hardware version
(TA-079 - TA-086) from firmware 2.81-3.03 to 1.50.

IMPORTANT:
  The Noobz team is strongly against piracy, and we're not just
  saying that to cover our butts. When you pirate games, you're
  removing the incentive for game and console makers to continue
  making fun things for us to play with. We are releasing this
  downgrader because we believe that using your PSP to its full
  potential and being able to customize it and run homebrew code
  is a fair use right that should be available to everyone.
  Please purchase games that you intend to play. Thanks!

------------------------------

降级要求：

如果要降级2.81－3.03版本的PSP你需要以下准备工作：

－将你的PSP电池电量充至75%以上。

－准备原生未打补丁的《侠盗猎车：自由城故事Grand Theft Auto：Liberty City Stories》(任何区域)，UMD内的升级程序在PSP内显示为2.00 update，就是以前用来引导eloader的那种GTA。