How to Install HydrOxyG3NMOD (Oxygen) Rom on AT&T Galaxy S2

Oxygen AT&T Galaxy S2

A great news for Galaxy S 2 AT&T version users: the immensely popular Oxygen Rom has been modded and ported to its AT&T sibling. It was earlier modded by Paradoxxx for Galaxy S2 international version i9100 under the name HydrOxyG3NMOD and the same has now been ported to AT&T version of galaxy S2, SGH-i777, by Skyler2Dope.

What we have here is another Android 2.3.7 based AOSP rom for AT&T Galaxy S2. It works quite well, and is fast and stable enough for daily use. Read on as we guide you through the procedure to install this ROM on your AT&T Galaxy S2.


This guide is applicable only for Samsung’s Galaxy S2 AT&T version (SGH-I777). Check your phone’s version in Settings – About Phone. It has to be “SGH-I777”  for this guide to be compatible with your phone. If it’s not SGH-I777, then simply do not try this.


Read everything carefully and thoroughly. The methods and procedures discussed here are considered risky and you should not attempt anything if you don’t know completely what it is. If any damage occurs to you or your device, we won’t be held liable — you only will be responsible, you’ve been warned!!! 

ROM Info:


  • Mixed UI ( Some Pngs from Ultimate Droid Roms, (With some cool themes inside Theme chooser apps ))
  • Better battery life & smoothness
  • Fully deoxed and zipaligned
  • Rooted and latest SU
  • Extended power menu
  • Apps and framework optimized and themed
  • A lot of hours of PNG edit
  • HeadSet Volume FIX. Ready to blow your EARS?
  • Fully touch recovery


  • Market
  • HTC IME V27 Custom
  • All stated above + ICS ringtones…

Removed: Many, many, things- this makes the ROM very fast.

Known issues: Hum, The HTC IME Mod may Crash the 1st time you will boot. But, It won’t do it again.

Pre-installation Thoughts/Requirements

  1. You must be rooted and have Clockworkmod (CWM) recovery installed. If you don’t have it, search for it and get it first.
  2. Installing/flashing this ROM will erase your apps and data. So, it’s a very important you back them up before proceeding further. To backup your apps and important data — bookmarks, contacts, SMS, APNs (internet settings), etc. this Android backup guide would help you. Restore APN settings if Internet isn’t working for you, after installing the rom. Your SD cards will not be erased, so don’t worry about those.
  3. Make sure your Galaxy SGH-I777 is sufficiently charged, at least 50% is recommended.

How to Install HydrOxyG3NMOD Rom on AT&T Galaxy S2 SGH-I777

Developer’s Note (read it, important!):

Recommendation is to backup anything you want to keep to your external SD card then take the external SD card out and leave it out until the ROM is booted and running.

For those having FCs with camcorder, please move all video files/photos from DCIM folder if you had taken any on Samsung firmware, or just rename that folder and CM7 camera app will generate a new one, restart and it’ll work.

Link to Original Development Page — Check for this latets version of the rom available for download, and changes made in the rom. Now, see the instructions below to begin the process.

  1. Download latest version of the rom from the official development page given above. Do not extract the zip file.
  2. Transfer it to your phone’s SD card.
  3. Power off your phone. Wait for 6-7 seconds after screen goes black.
  4. Boot into recovery mode. For this, hold both volume buttons and the power button for about 10 seconds and then release all three when you see the Galaxy S II logo disappear and reappear. This should boot you into CWM.
  5. Do wipe data/factory reset
  6. Do wipe cache partition
  7. Go to advanced and do wipe dalvik cache
  8. Go to install zip from sdcard » Choose zip from sdcard » navigate to and select the rom file you transferred in step 2 above
  9. Flashing of rom will start, and after it’s done, you’ll be back on recovery. Go back to main screen. and select Reboot System Now. It will take a few minutes to boot so please be patient.
  10. That’s it, you have the AOSP based HydrOxyG3NMOD (modified Oxygen Rom) on your AT&T Galaxy S2. Enjoy!

Do try this one out & let us know about your experience in comments below. If you have any doubts or face any problems, feel free to ask.


  1. uhhh….so it wouldn’t work on the canadian i727 skyrocket? I thought they were the same phone o-o

    1. Ah, nope, it won’t work.

  2. uhhh….so it wouldn’t work on the canadian i727 skyrocket? I thought they were the same phone o-o

    1. Ah, nope, it won’t work.

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