I couldn't care less.
I'm thinking about updating my PSP firmware. What I got now is 3.74 M33.
The idea is as follows:

1. Install the 5.50 Gen-A
www.atmaxplorer.com/2009/06/install-psp-custom-...

2. Install the 5.50 Gen-B
www.atmaxplorer.com/2009/07/install-psp-custom-...

3. Install the 5.50 Gen-B2
www.atmaxplorer.com/2009/07/install-psp-custom-...

4. Install the XGEN Updater Version 4. if this one doesn't work, install the XGEN Updater Version 4
www.atmaxplorer.com/2009/10/upgrade-gen-cfw-wit...

5. Install the 5.50 Gen-D
www.atmaxplorer.com/2009/10/install-psp-custom-...

6. Install the 5.50 Gen-D2
www.atmaxplorer.com/2009/10/install-psp-custom-...

Steps 1 - 4, step 6 are all the same:
1) download the archive. Extract the archive to the PC.
2) copy the PSP folder and replace your PSP "PSP" folder with the downloaded-extracted one.
3) start the update from the "Game" menu

Step 5:
1) after copying PSP folder to the PSP from the XGEN updater, copy 550.PBP into the root of the Memory Card
2) start 5.50 Gen-D upgrade
3) restart the PSP

Now that we got 5.50 Gen-D on the PSP, we should disable UMD support.
1. Switch the PSP off.
2. Holding the "R" trigger button, start the PSP. It will boot in recovery mode.
3. In recovery mode go to Configuration - UMD Mode.
4. Change the UMD Mode to "M33 driver -No UMD-"

Now you can play .iso ))

@настроение: 软件升级

@темы: PSP