Official ICS on rooted (but branded & sim locked) SGS2

[raducanmihai]

Hello. My name is Mihai, I live in Romania and I have an Orange branded & sim locked SGS2 (GT-i9100) on ICS 4.0.4
I flashed CF-Root-SGS2_XX_OXA_LQ5-v5.6-CWM5 and tried the CM10 but the little bugs annoyed me,so I made a restore to the original firmware.

During the period on CM10 I made some data speed tests (3G+ network) and I constantly got speeds up to twice bigger than the ones I get on stock firmware. The tests were made during the night,in the same position and the constant results (8-9 Mbs down on CM10 and 4-5 Mbs down on stock Orange firmware) make me believe that the culprit is the Orange firmware. I would also like to get rid of all the bloat.

My question is : can I install an official Samsung ICS 4.0.4 (not Orange branded) on my SGS 2 and do you think that my data speeds will be on par with the ones I've got on CM10 ?
I think my bootloader is still locked (i didn't unlock it).I assume that installing the CM10 unlocked it but I don't know if restoring the original firmware locked it back (if it is possible such a thing).

Thank you.

 

[ironass]

My question is : can I install an official Samsung ICS 4.0.4 (not Orange branded) on my SGS 2 and do you think that my data speeds will be on par with the ones I've got on CM10 ?
I think my bootloader is still locked (i didn't unlock it).

You can certainly flash another stock, unbranded, Samsung firmware to your phone. Whether or not it helps your speed really depends on the modem. For more information on modems, see, "Modems - Dummies Guide".

 

[raducanmihai]

Thank you for the quick response. Can I use any official ICS 4.0.4 or it has to be the one for unlocked and unbranded Romanian SGS2?
If I install, for example, the UK version, what happens? Do I lose Romanian language support ? Will I be able to update via Kies to the official JB 4.1 (in the near future, hopefully )?
Can I install, the Vodafone version as well (or any other official branded or unbranded 4.0.4 firmware) ?

 

[ironass]

Thank you for the quick response. Can I use any official ICS 4.0.4 or it has to be the one for unlocked and unbranded Romanian SGS2?

You can flash any stock Samsung firmware for your model of phone that suits your needs. Either branded or un-branded. Flashing a different firmware does not un-lock your phone.

If I install, for example, the UK version, what happens? Do I lose Romanian language support ?

Romanian language packs are found mainly on firmwares containing the XE and XF codes as shown, here.

Will I be able to update via Kies to the official JB 4.1 (in the near future, hopefully )?

No, you will not be able to use Kies to update if you flash a firmware other than that which came with the phone originally. You will however, be able to flash future updates via Odin, as described, here.

 

[raducanmihai]

Thank you, that makes it clear. I will flash a official Android 4.0.4 but I've red this will unroot my phone. Is is true?
I also noticed that the battery drain I saw on CM10 is still present after restoring the stock Orange branded firmware. I didn't wipe the dalvik cache before restoring so I assume this is the reason. What do you think and what whipe operations should I do before flashing an official Samsung firmware ?

I am confused about the reason why I get slower speeds on Orange branded firmware. In the link you gave me it said that the modem software is independent of firmware, so there is not an apparent explanation for the difference in data speeds.

 

[ironass]

Thank you, that makes it clear. I will flash a official Android 4.0.4 but I've red this will unroot my phone. Is is true?

Yes. You will need to either re-root, using the, "Rooting Galaxy S2 - Dummies Guide" or, you can, immediately after flashing your firmware via Odin and with the Auto-reboot option unchecked in Odin, immediately flash the .tar file for the Siyah kernel from here.

I also noticed that the battery drain I saw on CM10 is still present after restoring the stock Orange branded firmware. I didn't wipe the dalvik cache before restoring so I assume this is the reason. What do you think and what whipe operations should I do before flashing an official Samsung firmware ?

I would do a nandroid, Titanium and efs back-up before flashing, see post #2 of the, "Rooting Galaxy S2 - Dummies Guide", and do a Factory Reset.

I am confused about the reason why I get slower speeds on Orange branded firmware. In the link you gave me it said that the modem software is independent of firmware, so there is not an apparent explanation for the difference in data speeds.

The modem that is contained with the Orange firmware may not be the best modem for your network. You could, as you are rooted, just flash the modems mentioned in the, "Modems - Dummies Guide", without changing your firmware, to see which works best for your network and location.

 

[raducanmihai]

I've been busy the last couple of hours : I tried a Russian firmware ,I tried another Romanian firmware (branded by Cosmote carrier) and I've got slow (very,very slow) speeds (500 kb/s). Then I saw your thread about the leaked JB and I tried it.It works great,I have data download speeds up to 8-9 Mbs (like on CM10) and it also supports Romanian language (even if the code is XX,not XE or XF).
The problem I have now is : how to root it ? What kernel do I use and how ?

 

[Hawker]

PhilZ is the only one at the moment I believe