DuoX2 GS "Cromwell Bios Edition" Mod-Chip

Written by Zombie_X
December 2006


From what I have heard is that the Duo team have made some good mod-chips. This one still gets the job done. This will be my first forte into the world of Xbox mod-chips and will surely be a great experience! Or will it be?



  • Two 256.kb flash banks
  • Pre-flashed with Cromwell Bios
  • Easy installation
  • 6-7 Wire installation
  • Supports HDD up to 750gb



  • DuoX2 GS Mod-Chip
  • Pin Header



Xbox mod-chips are famous for being big and this one is close to the size of a credit card. It sports a white pcb and " DUO X2" text on the chip. The build quality of this chip is rather well and can stand up to a bunch of heat.



If you're wondering why I didn't cover installation it is very simple, there are tons of install note/guides out there and I didn't feel like posting stuff that is already out there. Well installation is a breeze at best with only taking a max of 10 minutes to install.

Well as far as it goes after you install the chip you have to flash the bios. At first when I started my Xbox back up I got it fragging on me. Fragging refers to a problem with the D0 wire or the LPC rebuild. I just went over the solder points again and got it to work. If your xbox is up and running then you can flash the chips onboard banks with any bios of your choice.

I used the Eurasia installer disc and I flashed the chip with Evox M8 bios (for Xbox v1.6). Flashing the bios is required since a fresh mod-chip doesn't have an illegal bios pre-flashed on it at all. Most chips have either Cromwell bios or other custom bios. Cromwell bios are mostly used for Linux and are only needed is you wish to use your Xbox as a Linux PC. You could also do a TSOP flash which is flashing the xboxes actual onboard bios. This is not recommended as it can kill your xbox permanently. What I would do is just install any bios which fit your needs. After that is done you can then run unsigned code and back-ups as well as install a lager HDD.

Another thing you can do is swap out the HDD for a bigger one. I swapped my 10GB HDD out for a 60GB HDD. Another advantage of swapping is being able to have more space for installing applications such as Linux and even unbanning your console from Xbox live.



Well I tried all of the Xport emulators and all worked as expected. I tired Super Mario War as well and it worked. I can play any region DVD/Game with no problems. XBOX Live is one thing I couldn't get working though and I was unable to connect to the servers with the chip on and off.

Now here is the part that no one should do unless you know what you are doing. You can use a program called "ConfigMagic" and it lets you edit the Xboxes EEPRom chip information. With this you can change your video modes as well as make a new HDD Unlock Key. Stupid me actually fried my Xboxes EEPRom and now my xbox wont boot at all. That sucks for me now. It is an easy fix as all I have to do is install a new EEPRom chip to the xbox MOBO (Mother Board).



It's a good chip and it may not have all the features that some people would want (like it's own OS/file manager and so on)but it's still a buy. Nice and simple installation with no extra soldering.


  • Ease of installation
  • Easy to upgrade
  • Flash Bios Upgradeable
  • Has two Bios Banks


  • No XBOX Live support
  • Limited features (chip itself)
  • No GUI or OS


Team Duo Web site