Sometimes Microsoft is just brilliant. The red ring of death mystery has been solved and the problem all goes back to Microsoft just being to cheap, which in turn royally bit them in the ass.
Microsoft wanted to save tens of millions of dollars when it came to contracted design costs. So they decided to design the GPU chip themselves and had Taiwan Semiconductor manufacture them.
Obviously that plan blew up in their face because while trying to save those tens of millions of dollars it ended up costing them over $1 billion dollars in warranty repairs. Wow, great idea guys.