Once the downgrade to 1.5 has been done lots of people don't know what to do next. Most annoyingly the newer games say they require an update to 2.5 again before loading. You sure don't want to re-upgrade after getting a nice 1.5fw PSP, so what do you do?

To solve this problem you use Devhook. Devhook essentially loads a different firmware (2.5 in this case) into the PSP's memory and temporarily runs it. This then fools games into thinking you have 2.5fw, but when you turn your PSP off and back on you're back to your 1.5fw. With the 2.5fw you can also use the web browser and all the other nice enhancements.

That's the important part - Devhook TEMPORARILY gets your PSP to use a newer firmware. 1.5fw is still there, but you must TURN YOUR PSP OFF to get back to it.

You're probably also wondering about ISO's. Game piracy is ILLEGAL and you should NOT do it. The only time using an ISO is acceptable is if you travel a lot (like me) and don't want to carry loads of UMD's with you.

There are a few tools that do this but I recommend you use Devhook. Follow these instructions and you'll be fine.


First thing, format your memstick in your PSP so we're starting fresh.



This RAR is basically a Dummies Guide to PSP Hacks - it skips a bunch of little techie steps you have to go through. Extract that RAR, there will be a PSP folder and a DH folder. You must copy these to the ROOT of your memory stick, eg: G:\ is your PSP, you copy them to G:\PSP and G:\DH.

Next make a folder called ISO in the root of your memstick. Copy your game ISO to G:\ISO.

Remove any UMD in your PSP.

Exit USB mode of the PSP and go to the Game menu in the PSP menus (the far right menu). Select "Memory Stick" and hit the X button. Scroll until you find "Device Hook" / "DevHook 0.42 Launcher", and hit X on it.

The PSP starts Devhook with the normal animation.

Devhook loads, this is a black screen with tiny white writing. IMMEDIATELY PRESS THE O BUTTON. If you don't, Devhook will reboot.

You'll get a popup menu. This menu lets you change the options you see in the bottom left of the screen.


UMD SELECT - Choose the ISO you want
UMD MOUNT - Choose ISO ANYUMD
UMD VERSION - Select 2.xx -> 2.00
FIRMWARE - Select 2.50
CPU CLOCK - Leave this at 222/111
BOOT SELECT - Select reboot XMB

Then choose Start from the menu. Devhook will load, your PSP will reboot, and it will look like nothing happened. This is fine! I like to check Devhook is working and has set defaults before starting. Go to the PSP system menu and check the firmware version, it should say 2.5! Shock! Don't worry, this is what Devhook does.

At this point you know Devhook is working and you can use the features of the 2.5 firmware. You only need to continue if you want to load an ISO.

Turn your PSP off completely, turn it back on. Go back to the firmware check, you'll be back to 1.5.

Put a UMD back in the drive AFTER your PSP is on, any one you like, but don't start the game. Wait for the PSP to recognise it and do the little animation thing where it jumps to the thumbnail of the game in the Game menu.

Go back to Devhook and load it. Quickly press O again, but this time choose the select ISO option only. Pick the iso you copied into G:\ISO earlier, then select Start.

If everything worked ok the ISO will load!

Essentially what Devhook does is redirect all access to the UMD to the ISO, which is why you need a UMD in the drive.



Once you've got this working you'll find everything else much easier. Newer games with need UMDEmulator, patches or similar, but I'll leave that to you to discover. Have fun!

By the way I wrote this guide because i noticed a lot of people did not understand how to install DevHook, Hope I've helped you there