Re: tech snippets

James Rogers (
Mon, 16 Dec 1996 13:13:10 -0800

>It seems, MMX multimedia instructions performance is distinctly inferior
>to vanilla PowerPC.

I agree. I think MMX is an excuse to have mediocre floating point
performance. I have always had reservations about specialty, high-level
instructions on a CPU. But then again, Intel has been doing this since the
i860 (which they are finally retiring). PowerPC has a solid floating point
architecture borrowed from IBMs Power 2 series, which also offered superb
floating point performance.

I think the P6 is Intel's first x86 CPU with adequate (although modest)
floating point performance. If I was going to do serious floating point
number crunching though, I would definitely go with PA-RISC, Alpha, or
PowerPC architectures. I think as Intel's architectures get faster, they
are going to find it harder and harder to sell their chips if they don't
seriously upgrade their floating point hardware. Fabulous integer
performance isn't enough for most high-end, computation heavy software,
especially in the realm of multimedia where you have a lot of realtime
signal processing and transforms.

-James Rogers