hey man
Check here
http://www.xbox-scene.com/tutorials.php?p=14|101|#101should give you everything you need to know about the matrix chip except for what version of xbox you can install it on. The Programmer Manual is where you will find the answer to your question. It will guide you thru how to flash it in there.
hope this helps.
p.s. if you stumble across anything that tells you what version of xbox the matrix can be used in please let me know, I have posted a question in this forum already.