Tag Archives: Xbox 360

11 mm in 1.25 nanoseconds

In 2004 I was working for Microsoft in the Xbox group, and a new console was being created. I got a copy of the detailed descriptions of the Xbox 360 CPU and I read it through multiple times and suddenly … Continue reading

Posted in Fun, Performance, Xbox 360 | Tagged , , | 8 Comments

Exercises in Emulation: Xbox 360’s FMA Instruction

Years ago I worked in the Xbox 360 group at Microsoft. We were thinking about releasing a new console, and we thought it would be nice if that console could run the games of the previous console. Emulation is always … Continue reading

Posted in Floating Point | Tagged , , , , | 16 Comments

Finding a CPU Design Bug in the Xbox 360

The recent reveal of Meltdown and Spectre reminded me of the time I found a related design bug in the Xbox 360 CPU – a newly added instruction whose mere existence was dangerous. Back in 2005 I was the Xbox … Continue reading

Posted in Debugging | Tagged , , , , | 49 Comments