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From: simoni@strat.Stanford.EDU (Richard Simoni)
Newsgroups: comp.sys.mac.hardware
Subject: Graphics accelerator theory of operation question
Message-ID: <1991May2.085707.11955@cascade.Stanford.EDU>
Date: 2 May 91 08:57:07 GMT
Sender: news@cascade.Stanford.EDU (USENET News System)
Reply-To: simoni@strat.stanford.edu
Organization: Stanford University
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How do graphics accelerators for the Mac (say for instance the Apple card
with an AMD 29000) gain their graphics speedup over a stock Macintosh?  That
is, do they use:

1.  Parallelism:  Graphics operations are off-loaded to separate processor,
allowing main processor to continue with other tasks.  (In the Mac world,
would this mess up the serialization of operations intended by the
programmer?)  For entirely graphics-bound operations, this parallelism
obviously won't buy much.

2.  Faster Graphics Processor:  Graphics operations are off-loaded to
separate processor which is faster than main processor.  Main processor
waits for graphics CPU to complete before proceeding.

3.  Other factors: e.g., block transfers on bus to increase available
bandwidth to memory, etc.

Thanks to anyone who can help enlighten me on this topic.  Apologies for
rehashing what I'm sure others have asked before.

Rich Simoni
simoni@strat.stanford.edu