heres a good walk through on rooting x2's BIG thx to XDA!
Originally Posted by DarkFalconX
This method works! There are only 2 differences in the commands (indicated in red):
Obtain the necessary files from the Atrix 2.3.6 link above
Extract the ADB-Fastboot package and root image to your C:\ Drive under a new folder titled ?root?
Put your device into Fastboot mode: ? Turn off your device. ? Hold down the power button and downward volume button until you see ?Fastboot? on your screen ? Push the upward volume button
Connect your phone via USB cable. Allow Windows to install the new hardware if this is the first time you have used Fastboot mode.
Open your command prompt (Start >> run ?cmd? >> enter)
Type the following commands
cd C:/root
fastboot flash preinstall root.img
fastboot reboot
Enable USB debugging (Settings >> Applications >> Debugging)
Type the following commands
adb shell
/preinstall/su
Allow Superuser access on the phone when prompted
Type the following commands
mount -o rw,remount -t ext3 /dev/block/mmcblk0p12 /system
cp /preinstall/su /system/bin/su
chmod 6755 /system/bin/su
PATH=/system/bin:$PATH pm install /preinstall/Superuser.apk
Congratulations! You are rooted!
This worked me also but I had to download superuser from the market first then follow the steps, and finally rooted