Hacker News Reader

The original Xbox was supposed to use AMD CPU as well, and parts of that remained in the architecture (for example it uses Hyper Transport bus), backroom deals with intel led to last minute replacement of CPU for an intel P6 variant.

View on HN

So last minute that the AMD engineers found out Microsoft went with Intel at the Xbox launch party [1]

[1] https://kotaku.com/report-xboxs-last-second-intel-switcheroo...

Wow! Good find!

Also, the security system assumes that the system has a general protection fault when the program counter wraps over the 4GB boundary. That only happens on AMD, not Intel.

This also led to a major vulnerability caused by different double-fault behavior between AMD and Intel known as “the visor bug”: https://xboxdevwiki.net/17_Mistakes_Microsoft_Made_in_the_Xb...

Reply on news.ycombinator.com