If you use ConfigMagic to edit your EEPROM -
it makes you unlock the HDD first, edit the EEPROM, then lock the HDD again.

If you use ConfigMagic to edit your EEPROM - to change a PAL XBOX into a USA one, original PAL games will no longer
boot. However, if you install UDE2, then you can still run original PAL games (007, etc.) - just via Evox's Launch DVD menu option (since all region checks are disabled by this point). Just don't try and play any XBOX!Live games this way - you'll get banned! So basically, this configuration isn't suitable for PAL XBOX!Live users.