How to speed up your Samsung Galaxy S with the Voodoo lag fix

We think the Samsung Galaxy S is one of the greatest phones of recent times. The design, screen and powerful hardware are everything we're looking for in our most important gadget. But there's a problem with the Galaxy S, and that's lag.

And it can be a considerable problem too, causing the phone to become unresponsive and frustratingly slow. There is a solution -- the Voodoo lag fix -- but it's really not for the faint-hearted, as it does involve moderate hackery and some risk of invalidating your warranty. We think these risks are tolerable though, especially compared to the performance boost you get from a lag-fixed phone.

The reason for the lag is that Samsung opted to use a file system called RFS. The fix converts the portion of the phone's storage where the OS and apps are stored to the super-fast EXT4 system. It seems Google agrees with this decision, because from Android 2.3, the file system will reportedly be EXT4 on all phones. That means, once 2.3 gets released, there'll probably be no need for any of these fixes.

Before you do any of these updates, please remember the following things:

• Backup your phone, contacts, images and music before you start. Remove external SD and SIM cards from the phone as a precaution.
• Make sure the phone is charged to 100 per cent, or is at least nearly full.
• Shut Samsung's abysmal Kies software. You might need this installed to get the correct driver to make ODIN see your phone. But make sure neither the app or tray service are running.

While this is all reasonably safe, it's not approved by Google, Samsung or anyone else. If it goes wrong, we probably can't help you and your phone might be permanently bricked.

By now, most of your Galaxy S handsets will have Android 2.2 installed. This makes this process harder, because Samsung now prevents the running of unsigned code via the recovery console, where it didn't previously. If you're still on 2.1, there's a good chance you can just download the Voodoo lag fix, put the update.zip on your SD card and install it from there, via the recovery console.

To do this, switch off the phone, then, when it's off, hold down the volume up and home keys and then turn the phone on. This will load into a screen with text. From here, you can simply press 'Apply update.zip' and if you have the correct firmware, the Voodoo fix will run and reboot the phone. Expect a cool robot voice to talk you through what's happening now and expect it to take some time.

Users with 2.2 or 2.2.1 will need to use a different method that requires you download a tool called ODIN. It's a bit scary, but our test proved it works well and quickly.

To make sure you don't brick your phone, you'll need to ensure it is in download mode. To get to this, turn off the phone, then while holding down the volume down and home keys, press the power button.

You should see an Android with a shovel and the words 'do not turn off target!!!'. If you flash the phone in recovery mode -- which you access in the same way, but with the volume up button held at boot -- then you might destroy the phone. This is a bad thing to do, and we can't really help you if that happens (and Samsung probably won't either).

With the phone in download mode, you should be able to connect it to your PC, open ODIN and see the device in the ID:COM box. You'll also get a message that says 'ADDED' in the lower left corner. If you don't get this, it probably means you don't have the Galaxy S driver, so you might need to install Kies -- groan -- to get it.

To flash with ODIN, you simply download 'Voodoo lagfix for Froyo, stable .tar' from the Project Voodoo site and load it with the 'PDA' button. Do not fiddle with other settings on this page, and never select the 're-partition' option: it will brick the phone.

Once you've done that, press start and you're away. ODIN will flash the phone, then it will reboot and talk you through what's happening. When the phone reboots, you should have the lagfix installed.

That should be everything you need. Remember if you want to disable the lagfix at a later date, you must make a folder called '/voodoo/disable-lagfix' on your SD card and then reboot the phone. If you want to update the phone later with Kies, you have to do this first or Kies won't be able to communicate with the phone.

If you've applied this fix, how did you get on? Let us know in the comments below.