I helped a friend of mine mod his v1.1 xbox using the matrix. First, I made sure that I used a v1.1 bios to flash the matrix with (I used the Evox 3.5 v1.1 bios). After spending about 3 hours trying to get it a green light, this is what I did:
1) First I filled in the lpc holes with solder. Trust me, this step will save you a lot of time.
2) Used magentic tape to isolate the d0 hole in order to not scratch up it or anything around it.
3) After reading many posts, I found that I was supposed to see a green flash, then red. That would mean that the matrix is properly aligned. Well, I NEVER saw green at all.
4) So I made sure that the d0 was aligned correctly, put the matrix into mode 2 and kept trying turning on and off the xbox to see if it ever said "Matrix Inside."
5) After a few times, it worked and everything is great!
My point is this, when working with a v1.1 xbox, you may NEVER see a green flash and then red after it. You may only ever see red. So maybe if you try this method, it may work for you. Any comments?