Norman Vine nhv at CAPE.COM
Tue Feb 15 02:22:06 EST 2005

Ed McNierney writes:
> Having (formerly) been in the business of building accelerated graphics
> hardware for a while, I'll respectfully disagree unless you've got some
> test data.  You're presuming that, for small patterned vectors, a
> graphics processor can "blow the doors off" a general-purpose processor,
> and that's really not likely to be the case.  These operations are quite
> simple, and the limiting factor tends to be memory bandwidth, rather
> than the drawing capabilities of the processor.  Preloading the pattern
> is trivial - it's manipulating the RAM that's the bulk of the work.
> 3D graphics rendering requires quite a bit of math, and the construction
> and acceleration of rendering pipelines is a BIG improvement.  But 2D
> line drawing, pattern filling and the like primarily consists of loading
> patterns and stamping them out into RAM, and most CPUs manage RAM
> read/modify/write cycles just fine.
> In fact, many of the recent major improvements in graphics hardware have
> focused more on improving the card's access to memory than on anything
> else.

"""Quartz Extreme uses a supported graphics card built into your Mac to
relieve the main PowerPC chip of on screen calculations.  This dramatically
improves system performance, making Panther much more responsive."""

Also expect the 'bus' to get quite a bit better in the near future :-)



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