Carmack announced:
"As DOOM 3 development winds to a close, my work has turned to
development of the next generation rendering technology. The NV40 is
my platform of choice due to its support of very long fragment
programs, generalized floating point blending and filtering, and the
extremely high performance," said John Carmack, president and
technical director of id Software

When Carmack speaketh, the world stands still and the games will stutter.