[LG Nitro HD] drumist:
IMPORTANT NOTE: There is a much easier way to root this ROM.

Skip this guide and use this method instead: http://xdaforums.com/showthread.php?t=1886460

I'm making this thread to explain the method for obtaining root privileges on the AT&T V20c ROM on the Nitro HD (P930). This really is the easiest way that is currently known, so please don't ask me if there is a simpler method.

This method will NOT allow you to install a custom recovery on your phone. If you want to install custom ROMs, you should follow the unbricking guide instead.

I should also make it clear that if you do follow the unbricking guide, you can install custom recovery and install HO!NO!'s flashable V20c ROM, which is already rooted. If you prefer this route, can you find more information about it here and here. The below process is only if you want to keep your phone as stock as possible with the only difference being that you will have root access.

Note that you will lose all your settings during this process!

1) Make sure you have the LG drivers installed. If you don't, install the drivers from this page: http://www.lg.com/us/mobile-phones/ATT_Update/index.jsp

2) Install the AT&T ICS leak ROM (v18f) here: http://rootzwiki.com/topic/26138-firmware-p930-udt-v18f-04112012-nitro-hd-ics-leak/ . Connect your phone to your computer, run P930_UDT_v18f_04112012.exe, and it will install the V18f ROM for you. If you can't get it to recognize your phone, then put your phone in download mode and try again. To access download mode, disconnect the USB cable from the phone, and make sure the phone is completely off. Then hold down the volume up button while inserting the USB cable. The phone will turn itself on (don't press the power button) and should say "download mode" on the screen. Then let go of the volume up button.

If you get an error when trying to run the v18f installer, right-click on the installer and select "Run as administrator". I'm not sure why sometimes this is necessary but other times it's not.

3) Once the V18f ROM has been flashed successfully, skip through the initial setup screens until you get to the home screen. Then go to Settings > Developer options and enable "USB debugging". Important: You must disconnect the USB cable before the option can be enabled! Then return to the home screen.

4) Reconnect the USB cable. Select "PC software" mode if it asks. Then download v20c_root.rar at the bottom of this post. Extract it wherever you want, then run TPSparkyRoot.bat. Your phone will automatically reboot multiple times during this process. After each reboot, wait until the phone is fully booted, then press a button to continue the program.

5) After TPSparkyRoot is finished, go to the KeepRoot folder and run Before.bat. After a few seconds, press enter in the command prompt window to close the window.

6) Next, go to http://www.lg.com/us/mobile-phones/ATT_Update/index.jsp and download and run the "LG Mobile Support Tool". If you already have it installed, you can simply run it. Follow along with the instructions to let it update your phone back to V20c. If you can't get it to recognize your phone, then put your phone in download mode and try again. (See step 2 above for instructions on how to access download mode.) Special note: If you have previously added the line 127.0.0.1 csmg.lgmobile.com to your hosts file as instructed by the unbricking guide, you must REMOVE the line before this step will work!

Important: After the phone finishes flashing, your phone will be stuck on the boot screen and will never finish booting. This is supposed to happen! Continue to the next step. If your phone boots up completely, something went wrong -- start from the beginning and make sure you didn't skip a step!

7) Once your phone is stuck on the boot screen, run the AfterROOT.bat from the KeepRoot folder.

8) Your phone will still be stuck on the boot screen. At this point, you should disconnect your USB cable, then pull the battery from your phone to force it to turn off. Reinsert the battery, then press and hold both the "volume down" and "power" buttons at the same time for about 10 seconds. You should eventually see a screen asking you if you want to perform a hard factory reset. Let go of the buttons when that appears, then press the power button twice to confirm.

9) If everything went correctly, your phone will now boot up normally with V20c installed and rooted! Check your apps to see if the "Superuser" app is there -- if so, you're rooted! Congratulations!

Please let me know if you have any issues or if you find anything is inaccurate in this guide. Thanks.

IMPORTANT NOTE: There is a much easier way to root this ROM.

Skip this guide and use this method instead: http://xdaforums.com/showthread.php?t=1886460