another xbox question

Most people will just hard wire in a Power Inverter via a relay.  But I've read many a posts of people complaining about interferance / noise.  The reason is that the Xbox being basically a computer, is very sensitive to voltage potential difference. You end up having to take it apart to ground the chassis and other components internally. To get a perfect audio / video signal. Furthermore, I've heard you need a heavier inverter due to the initial spike in current when first powering up the console.

Many people have taken thier PS2's apart and built a voltage regulator on a PCB.  I've never seen this done with Xbox but here is a link to one done with Playstation.  I'm not sure of the difference between the two systems, but the Xbox should have +/- 12v and  +/-5v.

http://www.dxav.com/tutorials/ps2_mod.htm

Someone else may be able to give you more details.

Good Luck