How to flash ThunderBolt ROM for the Galaxy S2 I9100G

There are many interesting treats coming out for Android, one of which is another Jelly Bean treat for the Samsung Galaxy S2 GT-I9100G. It's a modification built to transform your old Samsung phone into a brand-new Android device. Introducing the ThunderBolt ROM, another Android 4.1.2 Jelly Bean-based custom ROM for the Galaxy S2.

The ThunderBolt ROM, developed by XDA Developers member ALHussein Mohammed, lets you experience Jelly Bean with a Sony Xperia twist. Included in the ROM are some exquisite Xperia features such as the Xperia S theme, homescreen, keyboard, widgets and galleries. It's also packed with two custom kernels–Siyah and Dream. Check out our guide below to see how you can take advantage of this awesome ROM.

This guide shows you how to flash ThunderBolt ROM for the Galaxy S2 I9100G.

Warning

The instructions in this guide are intended for use with the Samsung Galaxy S2, model number GT-I9100G. Applying these instructions on another device or model may produce undesired outcomes.
The information in this guide is provided for instructional and educational purposes only. There is no guarantee that these instructions will work under your specific and unique circumstances.
Use these instructions at your own risk. We shall not hold any responsibility or liability for whatever happens to you or your device arising from your use of the info in this guide.
Read and understand the whole guide first before actually performing the instructions.

Requirements

A rooted Samsung Galaxy S2 I9100G with ClockworkMod Recovery installed.
- Check out our guide on how to root the Galaxy S2 running on Android 4.0.3 Ice Cream Sandwich firmware XXLPQ and install ClockworkMod Recovery.
Download the ThunderBolt Rom V6 (ThunderBolt ROM V6.zip, 508 MB) to your computer.
Make sure your phone's battery still has at least 70% power. You don't want the device to shut down in the middle of the procedure.
Backup all personal data on your phone to make sure you have a copy of your personal data (e.g., contacts, SMS, MMS, Internet settings, Wi-Fi passwords, and the like) in case the procedure in this guide erases such data.
- For backup tips, check our guides on how to sync your data to the cloud and how to create local backups of your mobile data.

Instructions

Installing from a Samsung ROM or another custom ROM

Copy the ThunderBolt ROM to your Galaxy S2′s internal SD card.
Turn off your Galaxy S2.
Boot into ClockworkMod Recovery by holding down the Volume Up, Home, and the Power buttons at the same time until recovery boots.
Make a NANDroid Backup by selecting Backup and Restore > Backup.
Select Wipe Data/Factory Reset > Yes.
Select Mounts and Storage > Format /System > Yes.
Select Install ZIP from SD Card > Choose ZIP from SD Card > select the ThunderBolt ROM ZIP file > Yes.
Select Wipe Cache Partition > Yes.
Select Advanced > Wipe Dalvik Cache > Yes.
Select Go Back > Reboot System Now.

Upgrading from an older version of the ThunderBolt ROM

Copy the ThunderBolt ROM to your Galaxy S2′s internal SD card.
Turn off your Galaxy S2.
Boot into ClockworkMod Recovery by holding down the Volume Up, Home, and the Power buttons at the same time until recovery boots.
Make a NANDroid Backup by selecting Backup and Restore > Backup.
Select Install ZIP from SD Card > Choose ZIP from SD Card > select the ThunderBolt ROM ZIP file > Yes.
Select Advanced > Fix Permissions > Yes.
Select Go Back > Reboot System Now.

Upgrading from this ROM’s ICS Version

Copy the ThunderBolt ROM to your Galaxy S2′s internal SD card.
Turn off your Galaxy S2.
Boot into ClockworkMod Recovery by holding down the Volume Up, Home, and the Power buttons at the same time until recovery boots.
Make a NANDroid Backup by selecting Backup and Restore > Backup.
Select Wipe Cache Partition > Yes.
Select Advanced > Wipe Dalvik Cache > Yes.
Select Install ZIP from SD Card > Choose ZIP from SD Card > select the ThunderBolt ROM ZIP file> Yes.
Select Go Back > Reboot System Now.