I did this modification a few months ago, but thought I would write a post about it. My xbox laser stopped working, and you have a few options when this happens
A) Buy a new xbox
B) Return the unit to get fixed by Microsoft
C) Fix it!
I choose option C.
I looked online and found lots of help, found out there is several different models of cd-roms in xboxs. The cd-rom I ordered off amazon was actually the wrong cd-rom, but had the same laser. So I had to remove just the physical laser assembly and replace it. I wont actually provide any instruction on how to replace the lasers, there are many websites out on the web that explain that better then I can, I just wanted to share a picture of the drive assembly and my experience.
