so you're attempting an install with the solderless adapter that has the little hook hanging off the side of it right?
First thing you want to try is a recovery. This involves moving the little switch on the side of the xenium chip into the recovery position. The point of a recovery is to 're-install' the Xenium operating system on the chip. Sometimes the OS gets corrupted and can be a cause of the 3 reboot frag. You'll need to make a Xenium OS recovery disc for this. There is a tute on how to do this here.....http://www.teamxodus.com/modules.php?name=...ewtopic&t=12562
you'll also need to get the Xenium OS to make to CD from, and thats avalable here.......http://www.teamxodus.com/modules.php?name=...download&cid=15
Try the iso version first, should be a matter of simply right clicking the iso image, selecting open with Nero. In nero, select 'write at once' and 'finalise disc'. Also, be sure to burn the disc as slow as possible and be sure to verify the data burnt properly. If is doesn't work, try different media (ie CD-R vs DVD-R vs CD-RW etc)
Whilst thats burning up, I'd pull the solderless adapter back out, get some iso propyl alcohol and a few cotton tips and re-clean all you LPC contacts on the motherboard as well as the d0 via you're inserting the d0 hook into. Also, if you're not sure if you have the d0 hook in the correct hole, check the downloads sections where those other guides are for a guide on locating your xbox d0 point.
Once you sort these dramas out, you're goig to want a copy of the 'The Iceguide', so you might as well as get that too if you don't already have it. This will guide you through the rest of the setup.