So first thing that you will need to do is make sure you root your phone. First go to this website and grab the newest rom for your version of S3.
Extract the stock_root67.tar from the .7z file you downloaded.
Use Odin, put phone into download mode [with phone off, hold vol. down + home + power ], connect to computer and open Odin.
once in odin click the PDA field and select the stock_root67.tar you downloaded.
Leave Auto Reboot and F. Reset Time checked.
click start and
when done let phone reboot.
If you have issues flashing with Odin please ensure you are using the microusb cable that came with the phone, users have had issues using other cables.
If you just want a stock, rooted phone with no custom recovery, no plans to flash custom roms, etc. then you can stop HERE.
To get clockworkmod recovery loaded so you can flash whatever you want, nandroid, etc then continue on....
Once rebooted you can grab a universal recovery that works on all sgs3 LTE variants from here: http://www.epiccm.org/2012/06/cwm-re...-variants.html
if you download this recovery you will need to extract this file (if you have issues extracting try removing the .md5 extension first) to get a recovery.img file and copy to your phone's internal /sdcard
However if you have the ATT model (not sure if this will work on Bell, Telus, Rogers, etc.), this recovery will see the extSdCard and seems better for our devices:
For ATT models use either this recovery or this touch recovery.
Then once that is done. We will need to flash the over clocked version of the kernel.
*************** ICE CREAM SANDWICH ****************
[ kernel file ]
The File ==> d2tmo/att TouchWiz kernel Mainline (OC'ed up to 1.62 GHz, should be 100% stable) <== The File ==> d2tmo/att TouchWiz kernel Ultimate (OC'ed up to 1.84 GHz, should be stable with most phones) <== 1. download the above file (via phone directly or to a PC) 2. copy the downloaded zip file to /sdcard/download/ 3. Open ROM Manager and select "Reboot into Recovery" and select "OK" 4. Once in recovery, select "wipe cache partition", select "Yes", then select "advanced", then select "Wipe Dalvik Cache", then select "Yes" again. Once finished, click the back button to go back to the main recovery menu. On that menu, select "Install Zip From SDCad", then select "Choose zip from SDCard", then go to /sdcard/download and select the downloaded zip file and let it run its script. 5. Once the script is done, select "reboot system now" Note: After FLASHING, the first reboot may take longer than usual, please be patient... After the first reboot, it may lag during initial load (let everything finish loading). Once everything is loaded and phone is ready for use, reboot the phone a 2nd time and the lag will be gone and everything should be silky smooth...
Now that you have done that.
You will have your device overclocked.
you may want to underclock it a bit just to make sure the device is stable.
SetCPU is a great tool to do this for you.
All of this will show that you are now running over clocked kernel and also rooted your phone. Though this does technically void your warranty the samsung counter does not get clicked so it looks like you never have. Which means if you need to return it just flash original rom on it and then send it back in. And your warranty is still good.
I hope this helps you guys.
Local Tech Repair Admin
PS if you like these roots and mods for your phone think of donating to those that developed them. The links to donate can be found on the respective links on this page.