While I was waiting to be able to power my experimental/half working xbox 360 I decided to see if I could easily get the firmware keys off the drive (Note: this not for piracy, the dvd drive is not working and I would like to replace it at some point.) First off, the dvd drive is a sata drive, however it does not run off of a sata power connector, instead it has a 12 pin connector where 10 of the pins are used. Pins 1-2 are not used on the connector, pins 3-4 & 6 are +3.3v, pins 5,7,9,11 are ground, pin 8 is +5v and finally pins 10 & 12 are +12v. I was able to figure out this pinout using the post here.
Sadly, I was not able to get the key off the drive this time, however I was able to create a simple xbox 360 dvd power adaptor which was powered by a standard computer power supply, or in my case a power adaptor for powering a single computer drive. In the picture you can see my simple power supply on a breadboard, most of this is straight forward, the only tricky part is you need a 3.3v regulator to drop the +5v line down to the 3.3v the drive needs. You can see the regulator at the top of the board with two capacitors keeping the output clean at a stable +3.3v. I did not use a switch to eject the drive, because from what I can tell, the drive motor controller is damaged and will only make a minor movement before freezing and not responding again.
While an interesting side project, it was somewhat pointless as now I can just use the 360 to power it. However it was convent to move this smaller adaptor vs a whole opened 360. Eventually I will take another stab at getting the key off, but not till I have had my fill of xbl arcade.