(based on ideas from the 411GB project by Ferrell + the multibios tutorial by |sys|)
Disclaimer: This mod is not particularly easy. I am NOT responsible for you destroying your xbox, or any other hardware. This is what worked for me, and I have done my best to document it. I hope it works just as well for you.
Update: Drive performance using a 4200 rpm drive can be poor. Check out this little comparison --> 4200 vs 5400
Note: This tutorial is geared towards people with a flashed TSOP, but it can easily be modified to work with the matrix, the enigmah, the xtender, a 29 wire homebrew, etc) I will try to mention different modchips throughout the tutorial.
Hint: For the matrix, leave the second dip "on" and use the point that I use for a19 on the relay to ground and unground the first dip. For other mod chips, such as the enigmah and xtender, you can use a dpdt relay where I use a spdt relay. This will allow you to switch both wires (i.e. 15 and 21 for the enigmah) to enable/disable the mods.
First of all ... what I mean by "dual boot environment" is the ability to boot one bios with one hard drive and another bios with another hard drive. It fits inside the existing xbox case and requires no external housing. This leaves you with 2 isolated environments which can be useful in many different ways. What ways you ask? Well considers these examples:
First environment: Original bios/drive Second environment: Modded bios/drive with homebrew software
First environment: Debug bios/drive with debug dashboard Second environment: Original bios/drive
First environment: Linux bios/drive with linux Second environment: Original bios/drive
Etc etc etc. The key is that both the bios and the drive are switched at the same time. You can see all the combinations of environments you can create. One particularly interesting use is that of a modded bios/modded drive and an original bios/drive. This would be ideal for those of you who want to have a modded environment and an original environment for xbox live! Having two seperate environments ensures that the original environment will never detect your modchip, or any modded data on your drive, because the two environments never touch each other. This will help keep you banned from xbox live.
It's quite simple really, a single DPDT switch, along with a relay, switches both the bios and the hard drive at the same time.
Still interested? Here's what you need:
- 3.5" Desktop Hard drive (original drive or other) (get anywhere)
- 2.5" Laptop Hard drive (Ideally 5400rpm, but 4200rpm seems to suffice) (get anywhere)
- A custom made IDE cable capable of three devices (see diagram below) (your local electronics shop)
- 44 to 40 pin adapter for IDE laptop hard drive (CompUSA or on the web)
- y-adapter for IDE power cable (radioshack)
- DPDT toggle (or slide, etc) switch (radioshack)
- 12v SPDT (or SPST) miniature relay (radioshack)
- a dual bios flashed onto your TSOP. (that is: the first 512k is one bios, and the second 512k is another)
- Some extra wire (radioshack)
- Some velcro, mounting tape, electrical tape, whatever it takes (radioshack of course)
- Solder, soldering iron, and some decent soldering skills. (radioshack and practice) :-)
The first thing we will look at is the IDE cable you need to either make or have made for you, it looks like this:
Note the positions of the connectors. The way the little "slots" are facing is important. Also notice the left connector is facing up while the rest are facing down. This seems to be just enough cable to reach the DVD drive, the laptop drive, and then the desktop drive. Be warned, too much IDE cable will result in poor performance with the devices.
Next we see a picture of the desktop hard drive, sitting in the mount that the original hard drive came in. You can use your original drive also, it makes no difference. It simply depends on what configuration you are trying to accomplish. Make sure you jumper this drive as MASTER!
Here is where things get fun. First make sure your laptop drive is also jumpered as master! Yes, you heard me right. Both the laptop and desktop drive should be jumpered as master! Then connect your 44 to 40 pin adapter to your laptop drive. Finally, using velcro, mount your laptop drive under your DVD drive. It should be roughly where mine is pictured below. Beware of some capacitors and such on the motherboard ... that's why mine is placed where it is.
Now you're ready to follow the ugly little wiring diagram below. Eventually I'll fix it, but for now, crank up the brightness on your monitor. I promise, there's colors! Forgive me, I used paint. I'm no artist. :-) As mentioned before, if you're using a matrix or a different modchip, you will need to change what is connected to the various states on the relay. Also, with an enigmah or a xtender, you will need a DPDT (or DPST) relay instead of a SPDT (or SPST).
And here you can see the actual "device" partially assembled. All that needs to happen is the relay needs to be wired to ground and a19 on the motherboard. (this is for the TSOP mod, for other mod, this would be different)
The IDE power cable that is already in the xbox plugs into the connector in the middle, the laptop drive gets plugged into the connector on the left, and the desktop drive gets plugged into the connector on the right.
Then, after soldering a19 and ground to their respective pins on the relay (or whatever it takes for your mod, etc etc), you need to mount all of it inside the xbox. I simply drilled a hole for the dpdt toggle switch, and mounted the relay with some double sided mounting tape. If you look closely below you can see it to the left of the case fan: (the junk you see on the top left are switches I already had installed prior to this project)
This is the back with the dpdt toggle switch installed on the left. Again, the two switches on the right are from things unrelated to this project. (enable/disable TSOP writing and enable/disable enigmah)
Next, you need to hook up your custom IDE cable and cram it all back inside the xbox. The cable should go from the motherboard, to the DVD drive, to the laptop drive, to the desktop drive. Yes, I realize you need to double back to get down to the laptop drive after the DVD drive, but it has to be this way. It works, but you may need to try a few different ways. Also, be sure the "short" end (the two 8" sections) goes towards the motherboard, and the "long" end (the 16" section) goes towards the desktop drive. Also, be careful not to break the nice connections you soldered to the switch or the relay while cramming your IDE cable inside the xbox. After the IDE cable is hooked up, you can then connect your nice new hacked y-adapter to the laptop and the desktop hard drive. The laptop drive gets the end with only 5v, and the desktop drive gets the end with both 5v and 12v.
Finally, I must mention the use of the multibios installed on the TSOP. The first 512k part of the BIOS will boot with the desktop drive, while the second 512k part of the BIOS will boot with the laptop drive. Plan your environments accordingly. With the matrix or other modchips... the laptop drive would go with the modchip on, and the desktop drive would go with the laptop off. You can of course change this by the way you wire your relay.
Once you have your TSOP setup correctly, or your modchip wired to the relay correctly, test the two environments by booting with the switch in both positions. If they both work, stuff y-adapter into the xbox (in the space at the top of the desktop hard drive) and then close it up. If things didn't work on your first try, check to make sure all your grounds are connected, and make sure you didn't snap any of your soldered connections to your relay or switch when you stuffed all the cables back into the xbox.
After everything is back up and running, you can see me using my "original" environment for xbox live!
That's it! I hope it all turned out as well as it did for me. If you need any help you can usually find me on #xblive and/or #xbins on efnet (Virtudude)
Thanks go out to xbox-scene.com, #xblive, #xbins, and all the hardcore hackers who dedicate so much time to this crazy stuff!