The official Bulldozer Status

[BrowncoatGR]

or maybe because amd is green just like the color of kryptonite ....

Actually i wasn't joking, it's true

Before it had either fancy brand names or even macho code names, AMD's
K-generation of processors,
beginning with the K5 in 1994, had their name inspired by Kryptonite,
the fictional element from comic books
that could bring the otherwise all-powerful Superman to his knees. In
this case Superman was Intel, whose
Pentium name was just catching on, but apparently no one took notice of
the fact that Superman is a good guy
and that only villains ever use Kryptonite. Yet the K has endured in the
names of various AMD chips for
nearly six years. AMD still turns out chips in the K6-2 family.

Also wikipedia