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Re: AGWPE



Tony Langdon wrote:
> 
> > The tragedy of the PC soundcard is that is has virtually no
> > buffer memory on-board.  If the CPU is even a little bit
> > late sending or grabbing data, you get a disruption in
> > the audio.
> 
> True, that would help quite a bit...

The sound cards really aren't that bad.  Or, at least
in the DOS days, you could setup a sound buffer of 64K.  Which
the sound card could DMA in or out of without the CPU.  And,
even at 44 kHz 16-bit Mono, is going to be, oh, 3/4 of a second or
so -- pretty long.  

(What does Commander Data say?  "Do an Android, that is an
eternity.")  

What screws all this up is the  virtual memory -- (at least 
this is what happens in games).  The
computer runs out of DRAM and starts swapping pages out to disk.  
And, the process of reading from the hard drive causes the code 
that fills the sound buffer to just fall behind, and this 
causes noise in the sound.  

An NT guru friend of mine says that NT is very aggressive 
in paging out code. That might make this problem worse, compared
to Me/98/95.

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